Frontier World

Nervously tapping her foot against the metal floor, Chase clung onto the harness tightened around her, the ten year old pup's breaths getting slightly more frantic as she felt the entire ship shaking and trembling. The young border collie's father noticed the girl's nervousness, a gentle smile on Sebastian's face as he laid his hand on the cub's knee, 
"Nothing to worry about, sweetheart. I've been through probably a hundred atmosphere entries in my life, they're always a little bumpy like this."
Chase did her best to believe her dad's reassuring words, giving an anxious smile and nodding as he patted her on the head, though she wasn't quite able to settle her nerves down even with the encouragement, gulping nervously as the entire ship jumped like it was slammed against the ground. The girl looked over to her side, surprised and downright envious to see her brother casually leaning back with a comic book in his hands, not even slightly bothered by the bumpy ride even though Mackenzie was a year younger than her, almost looking like he was about to fall asleep from boredom as he was being rocked from side to side by the shaking ship. The girl's mother was equally as unphased by the landing approach, Friday's eyes focused down on the pad of notes she was looking over, keeping herself busy with her work like usual. Of the entire family, Chase was the only one who hated flying, especially when it came to interstellar flights, having only left her home planet two times previously, usually preferring to stay on solid land rather than jetting off into the void of outer space. This time around however, the little dog didn't have much of a choice, as her entire family was moving off to a new planet. Of course, getting there wasn't the only thing that made the pup slightly anxious, as the planet they were about to land on was a frontier planet: a planet right on the outskirts of the colonised systems, with very little infrastructure or fellow inhabitants. The border collie family were among the very first wave of homesteaders heading off onto the planet to make it their own, with just a few dozen others living down there, scattered along the few different continents. Their task was to establish a spearhead community and to survey the lands, preparing the planet for further waves of settlers in the future, a task that left the family nearly all alone with very few people to call on in case they needed any kind of help. Chase wasn't sure if she fancied a life of being stuck in the middle of absolute nowhere, with the nearest shop or hospital a few light years away, but she was trying to keep her spirits as high as possible, even if the ride there was certainly putting quite the damper on that. Giving a nervous groan as the ship shook like it was about to fall apart, the puppy held her breath before it finally came to a standstill, letting out a relieved sigh as the captain of the ship spoke over the intercom, 
"We've landed safely, you can unbuckle your harnesses and head on out to your new home."

With a bag in hand, Chase stepped off the landing ramp of the ship, taken back by the rather breathtaking sights of the new world. Before her, a mountain range stretched out into the skies, lush green foliage growing out of cracks of earthy orange and brown rock, a small lake reflecting the bright sun like a huge mirror. The canine cub had seen plenty of pictures and video of the planet her family would be settling on, but none of it quite captured the true beauty stretching in all directions, alien and otherworldly yet comfortably familiar in ways that she couldn't quite put her finger on. Mackenzie bumped into the girl while she was standing in place and gawking at the sights, her brother giving her a smirk as he handed her yet another hefty bag to strap over her shoulder, 
"C'mon, I'm hungry, and we're not gonna get any grub if we don't get the kitchen set up~!" 
Chase followed her family down the landing ramp, glancing back to see the ship setting down the prefab house that it had attached to its belly, a huge set of arms driving down stakes into the stone ground to anchor the building into place before retracting back into the ship's compartment, giving the family a house ready to be moved into in less than five minutes. Helping her family unpack all the gear, supplies, and furniture they'd brought with them, the girl couldn't help but to constantly be distracted by the incredible landscapes in every direction she looked, her parents and little brother having to nudge her along several times to snap her out of it. Chase had always loved the outdoors and the wilds, and she was only now starting to realise how much she adored the idea of getting to explore a new land, especially as picturesque as the one her family was settling on. All throughout the unpacking, the girl was already planning her first hike out into the wilderness, eyeing up the nearby mountain range and the forest surrounding it, spotting several caves in the distance. 

Carrying a stack of books into her daughter's room, Friday noticed the cub pining for the wilderness, staring out her window with a small sigh. The woman stepped next to Chase, laying a hand on the puppy's shoulder, 
"Enjoying the view?" 
The young canine nodded, 
"Yeah, I can't wait to be done with this unpacking. I'm gonna head out right after dinner and go look around a little!"
With an unsure frown on her face, Friday thought about it for a moment before shaking her head, 
"No, I think it's best if you and your brother stick to the plains around our house for now. I promise, we'll all go out on a family hike in a week or two, but for now we just need to get settled in, your father and I will be pretty busy for the next few days."
"But… I can go out on my own, mom! I mean, I was camping out in the forest almost every month, without you or dad."
Friday sighed, 
"Yes, but that was back at A15. Honey, this is a barely explored planet. I'm not saying it'll be dangerous to live here, the government has had base camps here for over a year, but there is a reason why homesteaders get big incentives, you know?" 
Leaning against the window with a disappointed grumble, laying her chin down over her arms, Chase kept her eyes on the mountain range as her mom pet her back, 
"I promise, you'll get to run around to your heart's content all alone after we get a bit more familiar with the flora and fauna of this place, but until then you're gonna have to be a little more careful, okay?" 
With a big sigh, the border collie nodded, 
"Okay…"
Friday hugged the puppy, giving the girl a kiss on the cheek before turning to leave, confident that her daughter had understood the risks of being a homesteader as she went to continue unpacking. 

After a hearty dinner, made mostly of prepackaged and preserved ingredients that their father had done his best to spruce up in their modest kitchen, the two border collie siblings slipped away into their shared bedroom, sitting down side by side on Chase's bed. Mackenzie leaned back with a huff, patting his belly and smiling, looking like he was about to fall asleep any second, 
"Man, dad knows how to cook some good grub, huh?" 
Staring off through the window, the girl just shrugged, 
"Yeah…" 
Chase was still disappointed at being forced to stay at the house unless she had a babysitter with her, as if she was still some five year old little pup. The canine knew that a frontier planet like the one they were on did have the capacity to pose some risks, even with the fairly thorough scans and surveys that the government did before allowing homesteaders to move in, but she knew how to handle herself, her parents should've been able to see that. Noticing that his big sister was still bummed out by not being allowed to go out on her own, Mackenzie tried to cheer the girl up, looking around for a moment before spotting one of his boxes laying in the corner, hopping off of the bed and opening it up, pulling out a board game, 
"Hey, wanna play a match?" 
"Nah, not now…" 
With a sigh, Chase continued to look out the window, spotting the caves she'd been eyeing up in the distance, tantalisingly staring back at the cub as if to taunt her, getting an annoyed groan from the puppy before she suddenly jumped to her feet, a mischievous smirk on her face, 
"You know what'd get mom and dad to believe that I can take care of myself out there?"
Unsure if he liked the sound of what his sister had in mind, Mackenzie shrugged, 
"Uhh… what?" 
"If I proved it, with an afternoon trek to see that cave~" 
Now very sure that he hated his sibling's idea, the boy set down his board game, speaking in a low hush as he looked around nervously, hoping not to get busted by their parents for even talking about sneaking out without their permission, 
"What, are you crazy!? You don't know what's out there, and mom's gonna ground you for like a year if she finds out you went out without telling her!" 
Crossing her arms with a self-sure grin, Chase chuckled, having already made up her mind, grabbing her jacket before turning to her little brother, 
"Wanna come out with me? I'm gonna go check out those cool caves, they'll probably have all kindsa fun rocks and plants."
Immediately shaking his head, Mackenzie hopped up to his feet, 
"Nuh-uh, I want no part in any of this. If you wanna get spanked every day until you're in your teens, go ahead, but I'm just gonna go listen to some music."
Chase watched her brother walking out, scoffing with a roll of her eyes as she grabbed her backpack and began to stuff it with everything needed for a little hike, opening the bedroom window to sneak out without being seen by her parents. 

Slipping outside and taking a quick peek around to make sure she wasn't being watched, Chase took off towards the treeline, jogging with a big grin on her muzzle, her tail wagging behind her as the thrill of disobeying her parents made butterflies swarm in her stomach, giggling as she quickly dashed into the bushes. Jumping into the cover of the thicket, the cub squatted down to catch her breath, panting as she glanced back over her shoulder, continuing onward after seeing that no one was running after her, just as she'd hoped, her exit seemingly having gone unnoticed for the time being. Knowing exactly where she wanted to head to, Chase began marching towards the mountain range, eager to get there and explore some of the caves before it got dark out, thankful that the days were a bit longer on her new home than the 15 hour cycles of her previous planet. It didn't take the little girl long to begin seeing the rising rock face from beyond the branches and bushes, crawling through the thick brush as she trailblazed her way to the spot she'd seen before, coming to a series of cave openings dotted around the base of the mountains. Some were high enough that the border collie would've had no hope of reaching them without some rock climbing equipment, but a few were fairly easily within her reach, only requiring a little bit of clambering and careful footwork. Dusting herself off after pulling herself up, giving a determined sigh, Chase found herself standing at the mouth of one of the caves, a black void taking over just a few steps beyond the opening and stretching on from the entrance, making it seem downright infinite, with no end in sight. Having come prepared, the puppy reached into her bag and pulled out a flashlight, clicking it on as the blanket of darkness was shoved away, making the cave seem much less intimidating. Feeling an odd tingle in the back of the neck, as if some hidden and subconscious instinct was telling her that something was amiss, Chase stood at the mouth of the cave for a few seconds longer, peering into the depths as she scanned the darkness with her light, finally taking a step forward with a deep breath, 
"Well, I already came this far, no sense stopping now I guess…" 
Soon enough, the border collie had entirely disappeared within the cave, leaving only the tranquil scenery behind her, as if she hadn't ever even been there. 

Hearing her every footstep echo down the long tunnel, reflected back moments later all warped and distorted, constantly making her second guess whether she was just hearing her own steps or those of some stranger stalking her from the shadows, Chase couldn't help but to feel rather creeped out as she inched deeper into the cave. She usually wasn't one to get cold feet, having spent plenty of nights alone in pitch black caves and forests, but something about the knowledge she was on an almost completely unexplored planet made the trek particularly harrowing, leaving her grumbling to herself as images of some slimy alien jumping out at her flashed in the dog's head, 
"Damn Mackenzie and his stupid comics, getting me all creeped out…" 
Getting a thoroughly bad feeling about the entire endeavour, suddenly regretting going against her mom's orders, the girl decided he'd just check out what was hiding behind one last bend of the twisting and turning tunnel, and then she'd head right back home again. Coming around the corner, the cub was surprised to see a decently sized chamber rather than the cramped tunnels she'd been shuffling her way through the rest of the way, stepping in when she suddenly felt something oddly soft under her shoe, pointing her flashlight down and jumping back in disgust as she spotted what looked like a patch of greyish flesh on the ground, giving a startled shriek. Gathering herself slightly, the canine stared at the oddly alive looking blotch on the ground for a moment, grimacing as she noticed that it was actually bigger than she'd originally realised, following it with her light. The fleshy material led to what almost looked like an egg, a single brown pod as big as a microwave stuck to the cave floor. Disgusted, but simultaneously intrigued, Chase carefully stepped towards the egg, trying to stay off of the odd growths on the floor as she peeked at it, raising an eyebrow, 
"The ecological surveys didn't say a thing about anything like this."
Wondering whether she'd come across some completely new form of life, Chase took one step too far towards the pod, freezing on the spot with a horrified expression as it suddenly split open, a six-legged spider-like creature almost the size of her head leaping out at her, sporting no other discernible features besides a big opening underneath its belly, emitting a shrill screech. Screaming in terror, the cub didn't have the chance to move a muscle before the thing had already latched onto her face, its legs grabbing her head as the opening under it pressed against her muzzle, enveloping her face like some kind of a fleshy mask. The last thing Chase could feel was a large proboscis ramming down her throat as she gagged and choked, several slimy egg-like globs passing through it and getting forced deep inside of her as she fell to the floor, struggling and thrashing around as she desperately tried to pull the creature off of her face with no success, passing out just seconds later. 

Mackenzie sat next to his parents on the sofa, squirming and shuffling about, unable to find a comfortable position as his eyes constantly shifted to glance at a clock on the wall, counting the hours since his big sister had snuck out of their home. The sun had almost already gone down, yet the girl hadn't returned as she'd promised, leaving her little brother to nervously bounce his restless feet, debating whether to just hold out hope that she'd come back soon or finally reveal to their parents how she'd slipped out. Looking up from her notes, Friday noticed that her daughter was nowhere to be found, believing the cub to still be pouting upstairs, 
"I guess Chase is still mad about being told to stay put."
Sebastian sighed, staring out the window, 
"Maybe we should just let her go out. I mean, the survey teams explored this place pretty well, right? They don't tend to miss dangerous wildlife."
Friday shook her head with a sigh, 
"No, I don't know what I'd do if she was somehow hurt, we just have to stay firm on this. But we ought to get some free time and go camping together soon, that'll ease her tension." 
Feeling the pressure building more and more as his parents discussed the girl he knew was somewhere out there, Mackenzie finally broke. The boy just barely managed to keep from spilling Chase's disobedient activities, but he couldn't just idly sit by for a moment longer, jumping up to his feet with a slight look of panic on his face that he tried to keep hidden, 
"M… maybe I could cheer her up, I'll… I'll go talk with her!" 
Mackenzie ran off into the siblings' shared bedroom, making sure the way was clear before climbing out the window just as his sister had done, ducking down as he stared at the caves in the distance, remembering how Chase was staring at them, correctly guessing where the girl had headed off to. With heavy panting, the cub ran off after her, intending to bring her back home to lift the heavy load weighing down on his shoulders, clumsily stumbling through the thick brush as he disappeared into the forest. Almost two hours later, the exhausted border collie had arrived at the caves, looking around for any signs of his sister, his gaze bouncing between the multiple openings in the rock face, getting increasingly panicked about finding her when his sharp nose suddenly picked up a familiar scent. Closing his eyes and focusing on the faint scent, Mackenzie scrambled up to the same cave Chase had disappeared down, walking in, shuffling about in the dark while calling out for her, 
"Ch… Chase? Are you here? Hello!"
After a few minutes, the boy spotted a light in the distance, running and turning the corner only to find the girl laying on the floor, with the creature still on her face. With a horrified scream, Mackenzie quickly grabbed the unknown thing, yanking it off his sibling's face with ease, tossing the limp and dead creature against the wall, taking Chase's hand and struggling to drag her out of the chamber. In a frantic state, the cub checked that she was still breathing, shaking her as he screamed, 
"Chase! Wake up, c'mon!" 
Not knowing what to do, the boy used the burst of adrenaline coursing through him to pick up Chase, thankful she was fairly dainty as he hauled her over his shoulders, grunting as he began to run out of the cave as fast as his legs would take him, whimpering the whole way. 

Groaning as she slowly opened her eyes, all Chase could see was a blur of grey, her shallow breathing getting louder as the roof of her bedroom slowly came into focus, blinking as she sluggishly raised a hand in front of her face, rubbing at her snout. Before she could even properly wake up, another hand grabbed onto her muzzle, turning her head slightly as a bright light turned on, shining right in her eyes as the girl gave a pained whimper, squinting at the pen light before it turned off, revealing her mother sitting by her bed, a worried look on the woman's face. Friday let go of her daughter, gently petting the cub's head as she tucked away the pen light, making a note of the pup's pupil response as she spoke softly,
"How are you feeling, honey?" 
Still quite confused, and nursing a headache equal to a hangover after guzzling half a bar's worth of drinks in one night, Chase held her head while whimpering under her breath, trying to sit up, 
"M… mom? Where… am I?" 
Friday quickly put a hand on the cub's chest, keeping the little border collie lying down on the bed, 
"Just relax, you're at home. Do you know what happened to you?" 
Looking off into the distance, Chase tried reciting everything that she remembered, 
"Well… I kinda… ran away, to explore the forest and the caves. And I went into one, and then…" 
Though she tried to recall what happened next, all the cub's mind offered up was a blank void, unable to remember anything past stepping into the cave, a slight panic coming onto her face as she desperately tried to think back to what happened, 
"I… I don't know, I don't remember!" 
Friday hushed the quivering girl, her hands on the puppy's shoulders as she frowned, 
"It's alright, just calm down. Your brother found you, with some sort of an… animal attached to your face, though it was already dead by the time he arrived. How do you feel?" 
Chase took a deep breath, looking down at herself, trying to feel if anything was out of the ordinary, 
"I feel… pretty normal I guess, besides the headache…" 
The woman nodded,
"There really doesn't seem to be anything unusual going on according to my checkup either, everything looked ordinary when I examined you and ran some tests while you were unconscious. Of course, we don't have the latest medical equipment, and my medical training is more towards first aid, but…"
Friday thought back to the many rumours she'd heard, about how the government would snatch up just about everyone who had come into contact with unknown biological entities and lock them up in quarantine facilities, running tests for years at a time, sometimes making them disappear completely, 
"...well, I just… thought that maybe we could keep you here at home rather than taking you to the government medical facilities, if there truly doesn't seem to be anything happening to you."
Chase nodded, feeling slightly more calm, still panting lightly as she laid her head back down on her pillow, her hands resting on her belly as her mother caressed her cheek,
"Just rest for now, me and your father will be checking in on you, as will your brother. The boys are gonna be relieved to hear you're feeling alright."
With a nervous smile, Chase sighed, watching Friday getting up and walking to the bedroom door, stepping out as she closed her eyes, trying to calm down and maybe get some sleep, desperately attempting to dig up the memory of what had happened to her shortly before she'd lost consciousness, her head throbbing and a slight nauseousness settling over her. 

About a day after passing out, Chase was starting to feel much better again, getting out of her bed and up on her feet, even though she still couldn't remember what exactly had attacked her in the cave. The girl's parents had tried searching for the corpse of the creature to see whether they could study it in any way, but unfortunately neither cub could remember which of the many caves was it that they'd found the odd egg and the odd animal, forcing her mom and dad to simply sit by and make sure she wasn't affected by the attack in any way. Chase however wasn't nearly as worried about the entire thing, feeling just fine after a little rest, maybe even slightly better than she'd felt before passing out, refreshed and relaxed even as her parents continued worrying about her. After a few days of the adults keeping a close eye on her, the puppy was starting to feel slightly awkward with being babysat so closely, as well as a bit guilty since the two were supposed to be working hard, eventually managing to talk her parents into focusing more on their tasks rather than her, convincing them that she truly was just fine and didn't need to be constantly checked up on. Since their daughter really didn't seem any worse for wear, the parents decided that they'd respect her wishes and get back to their work, which required both to spend much of their time away from home, with Friday working on a research satellite orbiting the planet and Sebastian working at a mine a ways away from the house. The parents were slightly assured knowing that Chase wouldn't be all alone even with them busy at work, since her brother would be staying home with her, able to keep an eye on her in case there was an emergency of some sort. Thankful that she was finally getting out from under the watchful eye of her parents, with both leaving for their work early in the morning, Chase felt relieved. Of course, to get them to relax and not worry so much, she'd had to tell them a small lie of omission, as there was something a bit amiss about her body, a rather awkward change that the girl had begun to notice shortly after waking up. The symptom wasn't worrying enough for her to get her parents all worked up about it, but she wasn't quite sure what to think of it either, which is why she would've preferred to stay away from her little brother as well, feeling the odd symptom starting to flare up especially whenever the boy was close to her. 

Having already spent a couple of days all alone with her brother, Chase wasn't expecting anything out of the ordinary as she woke up in their shared bedroom once more, yawning slightly as she sat up, glancing over at the still sleeping boy. The girl however quickly started feeling rather foggy and unfocused, having to quickly toss her blanket aside as she began to feel sweltering, sweating as she panted softly, hot even in just the pair of panties she usually wore as her sleep attire. The puppy could feel her breath picking up, as did her heart, thumping like she was excited even though she didn't know why. Realising she'd been staring at her sleeping brother the entire time, Chase pried her eyes off of him and got out of bed, groaning quietly as she snuck off into the bathroom, confused about what was happening to her. Walking out, the pup noticed the most awkward of her symptoms, feeling the front of her panties sticking to her pussy lips as she shuffled along, glued to her slit by her sticky juices that drenched the pair, leaving her blushing as she quickly slipped into the bathroom. Unbeknownst to the young canine, the encounter with the creature had had a bigger effect on her than anyone realised, with her body having gone through an acceleration in very specific areas, triggering her puberty almost overnight and putting the bitch into her very first heat several years before she was supposed to be going through it. Of course, she didn't recognise what the odd sensation lingering over her was, having never even heard of heat before, since her parents thought it was best to let her grow up a little before having the awkward talk with the cub. Just one room over from the confused girl, another border collie was also starting to feel the effects of her heat, with Mackenzie's lower half waking up well before the boy opened his eyes, a sheepish grimace on his face as he groggily peeked under his blanket to find himself rock hard, his underwear tented up. The cub had gotten the occasional random boner before, but nothing quite this potent, an odd sensation akin to hunger making him feel restless as he climbed out of bed, thankful that his sister had already stepped out, not wanting her to see him in such a state. 

Sneaking out of the bedroom, Mackenzie intended to slip into the bathroom to quietly take care of the awkward situation in his underwear, opening the door only to find his big sister standing there, their eyes meeting in a moment of shock before both of their gazes started to wander down. The cubs had never been shy about being half naked, or even fully naked, in front of one another in the past, but this time around there was a tension in the air as the pair stared at one another in silence, Chase's scent burrowing into the boy's mind as he blushed. Even though neither knew what was going on, the girl's heat still had its intended effect on them both, leaving Mackenzie quivering and whimpering in desperation as his needy sibling stepped closer to him, neither saying a word as her eyes lingered on the throbbing red rocket pushing against his briefs, the tip poking out from under the band of the pair. With her mind going fuzzy from the heat taking over almost completely, all Chase could think about was the younger canine's manhood, salivating as she stared at him, not even thinking about how wrong it was for her to look at her own flesh and blood in such a way. Mackenzie was similarly affected by his sister's heat, not stopping her as she took him by his waist, gently pushing him up against the sink, leaning in close with their muzzles rubbing up as she reached down to push both of their underwear down. Chase grabbed the boy's cock by the knot, feeling it pulse and drool in her hand as he whined, the younger cub's tail wagging as she brought his tip to her soaking wet slit, both dogs moaning the second his dick rubbed up against her lips. Unable to wait for even a moment longer, still holding her brother by his knot, Chase bucked her hips against the boy and drove his cock deep inside of her, howling as he whimpered and moaned, Mackenzie's maw hanging open as he grabbed onto the sink for support, shaking from head to toe as he felt his big sister's sizzling hot mound gripping almost every last inch of his cock. Driven completely wild by her first taste of dick, the girl thrust against Mackenzie in a feral frenzy, wet slaps and frantic moans filling the bathroom as her juices drizzled down her inner thighs, soaking her fur as she pinned the gasping cub against the sink. Commanded by her feral instincts, Chase plunged her sibling's knot between her pussy lips, massaging him all the way down to the base as the boy exploded into a slurred mess of wails and screams, his legs giving out from under him as his sack twitched, unloading his seed into his sister's cunt. 

Moaning as she felt her little brother's load gushing deep inside of her, clinging to him as his cum spurted down her legs, pooling and dripping on the floor below as she tried to clench around his knot and keep as much of it inside as possible, Chase huffed while working almost entirely on her feral instincts. A female's heat usually would quickly begin to subside after being bred, but the girl barely felt any relief from the roll in the hay with her sibling, even as his cum overflowed from her slit. Thanks to the changes that her body had begun to go through because of the encounter with the creature in the cave, Chase was able to subconsciously sense that the boy was still too young for his seed to be fertile, which meant that he wasn't of much use to her quite yet, leaving her to wallow in the torment of her intense heat. Thankfully for the cub, she heard someone moving about outside, realising that it was their father coming back home after a long shift at his job surveying the mines, meaning that she had another male at her disposable, someone much more useful than the exhausted and dazed boy she was still tied to. Sebastian opened the door and stepped inside of his home, just about to yell out to his kids when the scent of heat hit him like a hundred ton ship slamming into him, causing him to freeze on the spot as the unmistakably feminine smell instantly made him lose control of himself, his dick slipping out of his sheath as he shivered in the doorway, barely even remembering to close the door behind him. Though he was still very vulnerable to the effects of the heat, the man's older age and experience did at least let him keep a better grip on his senses than what had happened to Mackenzie, panting and drooling but just barely able to think, confused as to what the source of the scent could've been. He knew that his wife wasn't supposed to get back from the research station until a few days later, and that she wasn't supposed to go into heat until a few months from now at the earliest. It also surely couldn't have been Chase, as the girl was still a few years away from her first heat. Befuddled and disoriented, Sebastian stepped further inside only to see Chase standing at the top of the stairs, staring down at him, fully naked with cum spilling from her blushing slit, licking her lips as he gulped. 

Chase slowly walked down the stairs and towards her dad, able only to stare at his package bulging through his pants as he took a few nervous steps backwards, sweating and stammering, trying his best to avert his eyes from his underage daughter's creampied pussy, 
"Ch… Chase? What… what's going on here?" 
The girl walked right up to her father, grabbing him by his shirt collar and giving a yank to pull him face to face with her, both canines panting together as she felt up his erection through his pants with her other hand, 
"Breed me~!" 
The cub's demand made the man shiver, breaking down his resistance as her hot breath washed over his snout, her voice filled with feral lust. Unable to say no, Sebastian grabbed up the girl and pushed her back, locking lips with her as he shoved her down on the sofa, swirling his tongue in her maw while grunting, ripping his pants open in a hurry, pulling out his girth while the pup hugged her, moaning against him. Chase felt her dad's dick slapping against her lower belly, glancing down to see the cock throbbing as a pool of precum collected in her belly button, his knot already swollen and ready to tie her. Without even asking whose cum it was that spilled from his daughter's cunt as soon as he had his tip inside of her, Sebastian use the previous creampie as lubrication as he plunged deep inside of the puppy in a hurry, still giving her a taste of his tongue as he laid on top of her on the sofa, taking her in missionary. Chase relished the feel of the man's girth stretching her out, a fair bit bigger than her little brother, squirming around underneath her father as he bucked almost balls deep inside of her, only barely able to hold back from immediately cumming as the snug hole squeezed around his manhood. Though he'd helped his wife get through many heats in the past, Sebastian had never experienced anything quite so intense and wild as his little girl's first estrus, completely under her spell as he ploughed into her hard enough to make the sofa rock and slam against the wall, their claws digging scratches into the cushions as the canines growled and moaned passionately, their previous relationship as father and daughter completely forgotten for a moment of pure carnal pleasure. Going as stiff as a board and whimpering as she felt her dad's knot gaping her pussy lips open, her back arching off of the sofa as she wrapped her legs around the man's back, both Chase and Sebastian came in unison, locked together as he emptied several days worth of fertile seed into the girl's hungry womb, unaware that the eggs waiting within were very different from the usual kind. 

Grunting hard as he felt like he was pumping an entire gallon of cum inside of his daughter, her tunnel clenching and squeezing down around his knot with every rapid heartbeat, Sebastian trembled on top of the howling and yipping little girl before finally going still, collapsing on top of her with a gasp. Chase rolled the man off of her, flopping on top of him as they both panted, his knot tying her, keeping in the flood of cum that he'd filled her with. Though her heat was starting to subside thanks to the fertile load sloshing around inside of her womb, the girl still wasn't quite feeling like herself, a different entity beginning to take her over as the seed that the cave creature had planted in her began to grow. With an odd look in her eyes, Chase stared down at her exhausted father while straddling his crotch, rocking her hips back and forth to milk every last drop of cum from him as he groaned. She could feel the eggs implanted within her getting fertilised by the man's sperm, a sly smile on the puppy's face as she finally popped the knot free from her slit, both border collies giving a sharp hiss as it slipped out from her tight grasp, spilling cum everywhere as she sat up straight. Chase watched as the worn out Sebastian's eyes rolled around in his head for a moment, before slowly closing, tired out by the intensity of his daughter's heat and passing out, just as her little brother had done only moments earlier. Grinning, the cub hopped off of her dad, walking with a slight limp and leaving a trail of cum behind her after the rough pounding he'd given her, the girl's cum-stained tail swaying behind her as she waddled into the storage room near the back of the house. There, the naked pup squatted down in the corner, gritting her teeth slightly and spreading her pussy lips with two fingers as she grunted, pushing like she was giving birth. A few globs of cum splattered onto the ground before being followed by something else entirely: a small egg similar to the one the girl had accidentally come across in the cave, except that this one was small enough to fit in the palm of her hand. Taking a second to gasp for air, Chase soon began to push again, straining as several more of the soft eggs plopped out of her, each fertilised by her father. After passing all of the eggs, the girl slumped back against the wall, huffing as she looked down at the clutch of eggs, smiling with a predatory glint in her eyes, knowing she just had to wait for a little while longer until they'd be grown enough to also infect the two passed out males laying all over the house. 

Helen sat down in the little break room, a steaming cup of coffee in the tabby cat's hands, taking a sip and letting out a relieved sigh. The cat had been busy at work the entire morning, since she was one of only three people working at the possible location for a mine, studying and surveying the spot to see whether it would be profitable to begin operations there. Midway through her cup of coffee, the woman heard a car approaching outside, stopping in front of the outpost as she glanced out the window, spotting Sebastian walking over. The man's shifts at the mine partially overlapped with Helen's, which meant that the pair spent quite a bit of time together, having become quite good friends already even though they hadn't known each other for very long yet. Sebastian stepped inside, greeting the cat with a nod as she waved, finishing her coffee before getting up, 
"Got here just in time, was about to start running through the samples from lot 15."
The border collie gave a smooth smile, hanging up his coat as he flicked out his security badge, logging in for the day, 
"Sounds good, let's get to business."
Helen chuckled and raised an eyebrow at the canine, oddly feeling like he wasn't behaving quite like himself, though she couldn't quite put her finger on it. Most of the time she'd been around him, Sebastian had been fairly quiet and timid, almost withdrawn, but just from a few second interaction the cat could tell that he was in a different mood this time around, much more confident and less sheepish. Though unsure about what had gotten the canine in such a good mood, Helen shrugged it off and beckoned him to follow her as she began marching back towards the labs on the other end of the facility, eager to get back to work. What the cat didn't see was Sebastian's eyes locked on her rump the entire time as he followed her, lagging a step or two behind to admire her perfect round ass, licking his lips as he quickly adjusted his pants to hide his growing excitement, not wanting to give away his true intentions too early. 

The afternoon went by as the duo worked in the lab all alone, casually chatting as they studied soil and rock samples, talking about how they were both settling in on the new planet with their families. Helen noticed how much more confident her coworker was that day, and she was liking the new side of Sebastian that she was getting to see, the hours seeming to just coast by as she talked with him. The border collie meanwhile was spending most of those hours eyeing up the cat, slowly but surely laying on the charm as he put his newfound charisma to work, intending to spread the gift that his daughter had given him. Before long, the pair were pulled out of their work by dinner break, walking side by side into the break room, grabbing trays of food with Sebastian taking a seat next to his coworker. As they talked more, Helen couldn't help but to notice the man staring at him, blushing slightly as she chuckled, 
"Why are you staring at me like that, do I have something on my whiskers?" 
Sebastian smirked and shook his head, 
"I'm just admiring your clothes, that top really suits you."
The cat was slightly taken back by his comment, her blush growing slightly deeper as she paused for a moment, unsure whether he was just being nice or trying to flirt with her. Helen knew that the man was married, he'd shown her some pictures of his family previously, but she wasn't sure whether his newfound confidence might've made him even more adventurous than she'd originally assumed. Realising she'd just been staring at the dog with a shy smile on her face the entire time, Helen let out a sheepish giggle and quickly looked back down at her food, 
"Th… thanks, I… I got the top right before me and my husband left to travel here."
Seeing that the woman was very receptive, Sebastian cranked up the heat even further, wanting to not leave his intentions unclear, 
"It's really beautiful… just like you are~" 
The border collie laid his hand on Helen's thigh, feeling her gently flinch at the touch before leaning into it, a barely audible moan coming from her as she gulped, her face as red as a rose as her eyes met her coworker's, 
"Aren't… aren't you married, with… with kids?" 
Sebastian nodded, 
"So are you." 
"This is… wrong, we shouldn't be… doing this…" 
Grinning, Sebastian leaned in for a kiss, 
"No, we shouldn't~" 
Melting into a puddle in the man's hands, Helen leaned into the kiss and threw her arms around the canine, moaning and shuddering as his tongue pushed into her maw, his hands down at her hip, feeling and groping around. 

Helen couldn't think straight as she felt the man lifting her up off of her chair, pure and unadulterated lust coursing through her veins as Sebastian grabbed onto the top he'd so fancied before, breaking off their kiss just long enough to rip it off of her, tossing it aside before going for her bra. Before the cat's mind could even catch up to what was going on, the bra had already dropped to the ground, the man feeling up her tits as she tossed her head back in a deep moan, quickly muffled by their lips pressing together once more. Helen couldn't really explain why she was doing this, searching for the reason herself even as she felt her panties growing damp, her tongue wrestling with her coworker's as she pushed a hand between his legs, feeling his rock hard package beneath. It wasn't like she was in any way discontent with her husband, she was getting plenty of action back at home, but the thrill of an affair with the border collie got the woman hornier than she'd felt in a decade, soaking wet and on the verge of a climax just from the over the clothes groping alone. Sebastian grabbed the half-naked feline and lifted her to sit on the break room table, moving his maw from the purring cat's mouth and down to her neck, kissing and nibbling as he continued further and further down, getting to her chest before starting to undo her pants. Her legs spread open and a hand on the man's head, panting as he teased her nipples with her tongue, Helen dearly hoped that the company hadn't installed any cameras into the break room as she watched the dog zipping her pants open, pushing her panties aside as he kissed her belly. Getting a whiff of the woman's excitement as soon as he had her slit out in the open, Sebastian knelt down and stuck his snout against her crotch, taking a deep inhale as she moaned, draping one leg over his shoulder and leaning back with a blissful look on her face, moaning as his tongue pushed between her pink pussy lips. Shaking and knocking over their empty trays and cups as she squirmed about on the table, Helen took full advantage of the facility being completely empty besides herself and the canine digging deeper into her cunt, screaming as loud as she could, grinding and humping her pussy against the man's muzzle as he ate her out, 
"Oh fuck! Keep going, just l… like that! Don't stop~!" 
The tabby couldn't believe what she was doing, only able to imagine the sort of trouble both her and Sebastian would get into if their partners ever found out about their illicit "break", but the naughtiness of the act only served to get her that much more worked up, feeling tingling all along her body as her tail twisted up into knots, shoving the dog's snout harder against her pussy while grinding her clit on his nose. 

Though he might've thoroughly enjoyed the taste of the feline's pussy, Sebastian made sure to keep his main goal in mind the entire time: to impregnate the woman and spread the gift that Chase had shared with him. With his purpose clear, the man kept lapping at Helen's slit, hearing her howl and moan, until she was right on the verge of cumming. At the very last moment, Sebastian pulled his maw away from the sopping wet mound, hoping to get her as needy and desperate as possible, standing up and wiping his soaked muzzle on the back of his hand as she looked up at him with burning desire in her eyes. The border collie stepped closer and pulled out his cock, lining the throbbing red rocket with the woman's entrance as she held up a hand to stop him, gasping as she stared at his cock, 
"W… wait, do you have a condom? We can't just… what if…" 
Sebastian shrugged, 
"What are the chances that you'd get pregnant from just one go? And besides, I'll pull out, I promise~" 
"I… I don't know…" 
Seeing the hesitation in the woman's eyes, the dog kept up his relentless assault, breaking down her barriers, 
"Or we can just stop, if you'd prefer that…" 
"No, I… I want it~!" 
Grinning at his plan working perfectly, getting the cat so pent up that she simply couldn't say no to anything, Sebastian grabbed her waist with one hand and her thigh with the other, laying her down onto the break room table as he leaned over her, muffling her moans with his tongue as he pressed inside of her. The first thrust was enough to get everything but his knot inside of the cat, her arms wrapping around him, her claws digging into his back as she writhed around in utter pleasure, her tight slit twitching around his cock as he pounded her. 

The table clattered and utensils fell to the floor as the two coworkers fucked, intertwined and sweating as they both thrust against one another, wanting to get deeper and deeper, lost in their little moment of taboo passion. Helen had entirely forgotten about her own family, able only to focus on the feel of the canine's thick shaft punching into her as she meowled like a feral back alley cat in heat, enjoying the affair so much that she came within the first few minutes already, riding out her climax while he mercilessly fucked her, leaving the feline gasping and whimpering. Helen's carefree pleasure didn't last for very long however, her eyes going wide in a mix of mind shattering pleasure and utter shock as she suddenly felt Sebastia's knot popping inside of her, cumming for a second time as she screamed while shaking, 
"N… no, p… pull out!" 
Moaning while firing off the first of several ropes of cum deep inside of the cat, feeling his tip teasing her cervix as he pumped her full, Sebastian smirked, 
"S… sorry, not much I can do now that we're tied, just l… lay back and enjoy it~" 
With her eyes rolling back as shot after shot of the man's seed rushed inside of her, Helen could do little else but bask in her second orgasm as she was filled up, unaware of the fact that she'd soon share the same fate as Sebastian and his two kids had shared earlier on. Impregnated by the border collie's potent load, it was only a matter of time before she'd fall under the control of the same creature that had gotten Chase, acting as the perfect way to spread the infection to her family and onwards. Groaning as he emptied his balls inside of the woman, grinning with the knowledge that she had no idea what was in store for her, Sebastian laid on top of her, panting as he kissed the equally tired cat, hoping to make absolutely sure that his seed would take hold, 
"Want to go for round two~?" 

Without knowing the whirlwind of events that has happened during her absence, unaware of her daughter being taken over by an alien infection, or her husband currently spreading said infection to his coworker by breeding her like a prize stallion, Friday was on her way back down to the surface of the planet. Due to her work taking place at an off-world satellite lab, the woman would spend several days up there before heading back home again, since daily trips up and down would be costly both in terms of money and time. Packed into a small shuttle with a few others working up in the laboratory, Friday gave a tired smile, eager to get back home to her family and see her cubs again, especially Chase, still worried about the encounter the girl had had with the unknown creature, even though it seemed like the pup wasn't suffering from any after effects. Taking a nap on the way down, resting up for the drive from the landing pad to her home, the canine woman took the opportunity to also quickly get changed in a bathroom stall once down on solid ground, wanting to get out of her stuffy lab wear and into something a little more alluring for her husband, feeling the effects of having to be separated from Sebastian for a good few days, stuck in cramped quarters with very little opportunity to satiate her active libido. Stepping out of the bathroom in a nice top and a gently suggestive skirt, Friday walked over to her car with a sly smirk, already planning on what she'd do to her husband after the cubs had been tucked into bed. Arriving back at the home as the sun was starting its dive down towards the horizon, the dog was rather surprised to see no sign of Sebastian’s car in front of the prefab building, having expected the man to be back from his shift at the mines already. Feeling an odd sense of hesitation creeping up her spine, as if she could somehow sense that something wasn't quite right, the border collie stood out in the yard for some time, her tail low as she listened to the near silence all around her, sighing as she pushed her unexplainable bad feeling aside and grabbed her bag, heading in. 

Stepping inside, Friday found the house oddly silent, as if entirely abandoned, getting another creeped out shiver as she looked around, calling out for her family, 
“Sebastian? Chase? Hello, anyone?”
“Hey mom!”
The woman jumped lightly at the voice coming from just a few steps away, spinning her head to see both of her cubs sitting on the sofa, almost hidden from view by the back rest, going unnoticed by their mother due to being completely quiet before she'd yelled out for them. Trying to calm herself down, putting on a smile as she stepped over to the pups, Friday pet her daughter, thankful that both seemed just fine, 
“Where's your father? I thought he'd be home well before I got here.”
Mackenzie smiled innocently, stumbling over his words for just a split second, as if he had to think about what he was saying, 
“He's… uhh… he called from the mines, there was some kinda emergency or something. Nothing like… bad, just a computer bug that wiped their work, so he had to stay there for some overtime.”
Friday sighed and glanced down at her skirt, her tail drooping down from disappointment, 
“Oh, that's a shame… “
Both cubs nodded as the woman narrowed her eyes, growing increasingly suspicious, spotting that her cubs weren't acting like their usual selves. She thought that maybe something had happened, something that they were trying to hide, maybe some sort of mischief that went on while both her and Sebastian were gone. She even swore that she caught both of the puppies eyeing her up, in the same way she'd hoped her husband would've been admiring her short skirt if he was home, though she quickly pushed such ridiculous thoughts out of her mind, thinking she was just getting jumpy due to the new locale and the recent events. Before the canine could ponder it for too long however, Mackenzie jumped up from the couch with an excited smile, 
“Oh yeah, I just remembered! I found something really neat, you gotta come check this out mom!”
Curious, the woman followed behind her son as he led her towards the storage room, not spotting the grin on her daughter's face as Chase watched her walking away. Both border collies stepped into the room before Mackenzie flicked on the lights, revealing a whole clutch of the same eggs Chase had found in the cave, a dozen of them attached to the floor and the walls. Frozen still in shock for a moment, the mother screamed in terror and was just about to turn to run away when the closest egg split open, a familiar creature jumping out and latching onto the woman's face, causing her to fall to the ground and writhe around as its proboscis rammed down her throat. Mackenzie watched his mom thrashing around on the floor, a smirk on his face as he slowly closed the door behind him, a bump appearing on the front of his pants as his eyes wandered down towards the helpless woman's skirt while her muffled screams filled the storage room. 

As Friday's squirming slowed down little by little, Mackenzie nudged the woman to her back with his foot, zipping his pants down as he knelt between his mom's legs, grinning while pulling out his stiff cock, deciding to hurry the woman's insemination along while she was still being implanted with the eggs. Growing weaker by the second, choking as she felt several of the small eggs being shoved down her throat, Friday could do nothing to stop her son as he pushed her skirt up, tugging her panties down to her ankles before immediately mounting her, stuffing his face between her tits as his knotted length nuzzled against the wet slit, soaking wet for who she'd hoped would've been his father. Pushing Friday's top up, feeling up her chest and belly while kissing her breasts, Mackenzie thrust inside of her, feeling her writhing around picking up again as she screamed against the creature clinging to her face, helplessly flailing about while her son moaned with a thoroughly satisfied smile on his face. All the older canine's kicking and squirming managed to do was to cause her to accidentally hump and grind against the cub's cock, only working him towards the climax even faster as he panted. The boy heard the door to the storage room slowly creaking open while he was nearly balls deep inside of his mother, looking up to see Chase standing in the doorway without any pants on, a finger inside of the girl's cunt as she watched her brother breeding their mom with a smirk, staying silent and letting her little sibling perform in peace while she enjoyed the show. Feeling Friday starting to go limp underneath him again, almost passed out from the creature laying its eggs inside of her, Mackenzie doubled his efforts, grunting as he pinned his mother down by her wrists, hammering at her pussy as hard as he could, gritting his teeth and holding his breath until his knot punched inside, getting one final twitch from the woman before she lost consciousness. Although Friday might've passed out, Mackenzie was feeling more alive than ever, howling with his tail wagging as he emptied a huge load in her pussy, already starting to overflow over his throbbing knot as his sack pulsed, groaning until falling flat over her, panting with a smile. Chase knelt down next to the pair, cupping her brother's chin while still deep in her own pussy with her other hand, licking her lips as she watched cum drooling from their unconscious mother's slit,
“Got enough left for me still? I have another load of eggs in desperate need of some fertilisation~”

A few weeks later, bouncing along countless communication buoys, travelling from the frontier planet all the way to the very heart of civilisation, a message sent by Sebastian arrived at the busy headquarters of the mining corporation who was planning to set up an operation on the fledgling colony. Such an endeavour would mean an instant rush of new citizens and workers onto the planet, flocking in for the numerous jobs that such an operation would offer, something that the border collie was very aware of. Getting a notification for an incoming message, a manager sitting in his office turned to his computer monitor, clicking a few buttons on his keyboard and sitting back as a video message opened up on the screen, showing both Sebastian and Helen standing in the mineral survey labs. The pair had big smiles on their faces, doing their best to conceal their more sinister and devilish grins as they waved for the camera, with the canine stepping up to speak, 
“We've had a real breakthrough here in the labs, and we thought you'd be delighted to hear about it as soon as possible. Thanks to a few lucky breaks, we managed to get all of the tests done well ahead of schedule, and guess what? This place is absolutely loaded with minerals, from rare earth to titanium, it's a real goldmine!”
Helen put her hand on her coworker’s shoulder, trying not to shiver from the load dripping from her slit that he'd pumped in her a few minutes earlier, 
“According to all of our tests, this planet might actually be home to the richest deposits found anywhere so far!”
With a nod, Sebastian tapped to a chart he was holding in his hands, filled with data they'd carefully forged, 
“I will of course be sending you all of the results along with this message, but I must urge you to move fast, get the operations set up here, and send some people over as soon as possible, we don't want to lose this motherlode to some other company.”
The manager immediately sat up straight as the message ended, staring at his computer screen with a huge grin before pumping his first with a victorious yell, quickly running out of his office and shouting at his assistant, unaware of Sebastian’s true intentions, 
“Lily, get the board on the horn, and call up the resource office, we need to have ships moving workers to that planet yesterday! Send every available hand we've got!”