Insomnia
Written by: minoan

December 11, 1997

“Good night Matt! Sleep tight!”

“Night Mom!” Matt called back from underneath his bed cover. His mom enforced a 10 p.m. bedtime for both him and his sister, but she usually stayed up a little later. In the past Matt would usually stay awake for a few more hours playing his Pretendo 64 with the TV on mute so his mom wouldn’t hear, but for the past few weeks something else was keeping him up past his bedtime.

The 14-year-old Shire horse and his 18-year-old sister Jennifer had been fucking since Thanksgiving. This wasn’t just an occasional thing; in the two weeks since they’d started, not one day had passed in which they hadn’t had sex at least twice, and today had been no exception.

Matt had been having trouble getting enough sleep lately. It was like when he got a new game for his Pretendo – while he’d normally sleep in and stay in bed as long as he could, whenever he got a new video game the excitement of playing would  wake him up early to get in some extra gaming hours before school. He’d stay up late, and when he finally did sleep he’d dream about playing.

His sister was having the same effect on him now. Sex was his new addiction, and the prospect of more was making him wake up while it was still dark outside.

Early that morning, before his alarm even rang and while the sun was just beginning to rise, Matt woke up with a full erection. In his case that meant an absolutely gigantic black shaft riding up the entire length of his light gray-furred stomach and chest, reaching slightly higher than his black nipples and nearly to his neck.

He rolled over, looking at the red LED glow of the clock radio on his nightstand – 5:27 it said in sharp right-angled lines. Was that too early? Would she be mad? He hadn’t gone in there before that extra red line changed the 5 to a 6, but maybe it was close enough.

No, he thought. Too early. He rolled over on his stomach trying to get his erection to subside, but the pressure from his chest pressing his cock into the bed was more stimulating than arresting. Before he knew it he found himself gently rocking his hips, thrusting into the tightness between his own chest and his mattress.

That was no substitute, of course. He turned over again with an unhappy grunt to look at the clock again. 5:31. Fuck it, he thought. That was close enough.

Jennifer was still asleep when he opened the door from their bathroom to her room. He found himself tip-hoofing up to the bed in the darkness even though he was about to wake her up anyway. It still felt weird coming into her room like this; a few short weeks ago this would have been unthinkable. Now it was almost impossible to imagine a morning without it.

Matt pulled back on the pink comforter and sheets. The first subtle grays of twilight were filtering into his sister’s bedroom, just enough light for Matt to see her face and pinpoint the instant she woke up. That might have been his second favorite part, after the fucking – that golden moment when she opened her eyes and realized there was a 14-inch horse cock staring back at her.

Matt saw her broad, horny grin right before she leaned forward and wrapped her lips around the flat end of his dick. He put his hand on her head, feeling her mane between her equine ears as she bobbed gently. It took less than a minute for him to start pulling the comforter back further. Jennifer didn’t even change positions, still laying on her stomach; with a slurp she stopped sucking her brother’s cock and unceremoniously started taking her plaid pajama pants off underneath the covers. There was no hint of enticement of teasing – this was purely functional, removing an obstacle so that her little brother could mount and breed her.

Jennifer pushed her pants further under the covers, wedging them in the corner of the bed with her hoof. At the same time Matt – totally naked – crawled up onto the bed and under her sheets. He smeared a trail of precum on the bedspread and across his sister’s thick thigh as he shuffled into position.

She was so much bigger than him; nearly 8 feet tall to his 5 feet and change, 350 pounds of muscle to his much less athletic 140. He lifted his leg over her thigh, which itself was as thick as his entire body. It was pitch black underneath her sheets and covers, but Matt didn’t need to see what he was doing to find his way between his sister’s legs. He learned that the first time they’d fucked at the Halloween party.

It was so much warmer under his sister’s covers and between her legs than it was outside. Matt ran both hands through the short gray and white speckled fur on the back of her bare thighs, slowly feeling them up, up to the modest ridge of slightly softer flesh that marked the transition from leg to butt.

He squeezed two handfuls of his sister’s incredible ass. Her butt was the perfect compromise of firmness and bounciness, despite its size – Matt’s entire butt wasn’t even as big as one of her cheeks.

Matt felt Jennifer wiggle her hips, enticing him further. During the past few weeks the power dynamic between them had been shifting. It had been happening slowly, bit by bit and moment by moment, but Matt knew it for what it was. He may have lusted after Jennifer, he may have wanted her body, but she needed his cock. Realizing that, Matt was becoming more and more confident. This perfect, massive ass he was groping wasn’t something his sister offered to him sparingly and he was lucky to get – it was something he could claim as his own whenever he wanted. Thanks to her he knew how truly special his freakishly huge cock was, and he understood that due to her social situation his was the only cock she would be able to get. All of this gave him a huge amount of control over her, which he was only beginning to understand.

Jennifer didn’t even mind. She was finally getting cock on the regular for the first time in months, and on top of that it was the best she’d ever had – that was all she really cared about. Never mind that every time she got it she was committing incest with her 14-year-old brother, the one she thought was a dorky loser just a few weeks ago. Never mind that she was slowly becoming his personal slut, or that she was pregnant with his foal and still hadn’t told him. She was getting the cock she was addicted to and that was all that mattered.

She smiled and sighed happily as she wiggled her butt for her brother to play with, still groggy with eyes half-closed. Jennifer was letting Matt get away with more now than she would even a week ago. She actually liked these wake-up calls – it was as if a little sex-gremlin crept under her sheets every morning and had its way with her body, used her like a toy, then skulked away into the darkness before the sun rose. It would be easy to imagine that these were simply dreams if she didn’t wake up with wet thighs and cum oozing from her pussy.

She felt her brother’s hand on it now. She bit her lip as he stroked it, she lifted her butt slightly as his fingertips entered her. Yes, she was letting him get away with more than she would have even a few days ago, but it was a slippery slope that she couldn’t stop sliding down now if she wanted to.

Jennifer’s slippery slit offered no resistance as four fingers slid into her to the knuckles. Matt didn’t hesitate. He pressed further, his palm and thumb sliding in easily.

Matt felt his sister’s warmth envelop the thickest part, and before he could restrain his entire hand was inside her. He pushed further, wrist-deep in his sister’s big equine pussy, and the desire to see just how far he could push in overtook him. His cock really was about the same size as his entire fist and forearm, up to his elbow. Could he push his arm into her that far? She wasn’t stopping him. There didn’t seem to be any reason why not.

Methodically he pushed deeper, inch by inch, feeling the heat, pressure and wetness of his sister’s pussy wrapping around his arm like a glove. By the time he got to his elbow Jennifer was noticeably pushing back, eagerly accepting inside her anything Matt wanted to give.

He started working his arm inside her, forward and back. When she didn’t complain his fisting got more forceful, pumping in and out from his elbow to his wrist. Incredible, he thought, that something big enough for him to fit his arm inside felt so tight around his cock. At that moment he felt Jennifer’s equine vulva wink around his hand. Almost instantly it happened again, this time accompanied by faint squishing noise, and that was too much for Matt to contain himself to explore any option except one.

Jennifer felt Matt almost rudely pull his arm out of her. He clumsily flopped on her back as his wet hand took hold of his cock, guiding it in a quick motion to the hole the hand had just emerged from. With another heavier flop he dropped his entire weight on her, with it he thrust his thick black and speckled-pink cock inside.

“Ohh...” Jennifer moaned, trying to stay as quiet as she could so that she wouldn’t wake up their mom. Matt was still indelicate, hasty… sometimes a little too rough, seeming to care only about fucking hard and fast and cumming deep inside her. That’s how all colts are by nature, she knew – just the instinct to breed a mare. He’d expand his repertoire with more experience, learn to think about the mare’s needs as well as his. Fisting her was a good start. In the meantime, there was still something primal and bestial about these breeding sessions with her brother that she loved. It wasn’t just the fact that it was her brother, though that was part of it. There was just something about freely and easily offering her pussy to a much younger, much smaller colt that she found highly erotic.

Matt was still completely under Jennifer’s covers as he pounded away at his sister prone-bone, her ample butt providing cushion every time her drove his cock down into her. Jennifer wrapped her hands around her pillow; she’d barely had to move at all since she woke up, still laying on her stomach. All she’d had to do was take off her pajama pants. Her little brother was doing the rest.

Matt’s nose barely made it to his 8-foot-tall sister’s strong shoulders as he sprawled on top of her. The air underneath the covers was getting stuffy so he lifted his body up from her back and flicked his muzzle to toss the sheets back off his head, his nostrils flaring as he breathed in the cool fresh air.

His hips were on autopilot, bouncing rhythmically on his sister’s huge butt as his cock slid in and out of her drenched pussy. The plap-plap-plap of his fist-sized balls slapping against her rear several times a second underneath the sheets was the only sound in Jennifer’s bedroom.

Matt lowered his body back down onto his sister’s back while his hips kept bucking, feeling the warmth of her body on his stomach and chest as his hands slid across her broad shoulders and out to her arms, tracing the contours of her muscles. He turned his head to the side, pressing his cheek against her upper back, and his nostrils flared again as he inhaled her scent. 

Matt closed his eyes. He could feel the slight tingle in the tip of his cock that would soon explode into orgasmic bliss – he was getting close.

Matt may have been getting laid every day for the past several weeks, but his real experience with and understanding of sex was still very limited. He didn’t know, for instance, that most mares don’t appreciate it when a colt cums inside them without warning and without permission. He didn’t even have a basic understanding of how pregnancy worked, not really. Jennifer had told him it was safe, and she wasn’t stopping him, so it must be safe, right?

Jennifer knew it wasn’t safe. Of course she did. Or rather, she knew it wouldn’t be safe if she weren’t already pregnant with her brother’s foal. She wasn’t telling him for a combination of selfish and self-serving reasons, but she didn’t consider the damage she was doing to him when it came to how he thought about sex. ‘Safe sex’ was not a concept Matt had any real understanding of, thanks to Jennifer – a fact that would profoundly change Matt’s life over the coming months.

Matt opened his eyes and saw the alarm clock on his sister’s nightstand. It was exactly the same model as the one in his room; they’d both gotten them at the same time, one of the dozens of random matching gifts their grandmother gave them at Christmas every year. What would she think if she knew her precious, ‘innocent’ grandchildren were fucking right now?

One of the glowing red lines on the clock disappeared as the LED display changed from 5:38 to 5:39. Matt’s hips were moving faster. He gripped tightly onto his sister’s strong arms, each bicep nearly as big as his thigh. He closed his eyes again.

Without warning or permission he thrust forward a final time, plunging the entirety of his 14-inch cock as deep into his sister’s pussy as it would reach. The end of his equine cock swelled, flaring deep inside her like a flowering dimpled mushroom as Matt ejaculated, a torrent of hot, potent cum pouring into Jennifer’s womb.

“Ahhn...” she mewed in quiet ecstasy, trying her hardest to remain silent to not wake up their mom. Yes, this was wrong. Yes, she was corrupting her brother, and yes, it would have consequences in the coming months that neither of them considered, but in this moment that didn’t matter. Her eyes rolled back in her head and for the moment her mind went blank. She felt the cock deep inside her twitch again, felt the second mammoth pulse of cum filling her up. This was the best feeling in the world. It was like a drug, and she’d do anything for another hit. Nothing else compared to being bred, and any cost was worth it, consequences be damned.

Five. Six. Seven pulses of cum, each as powerful as the last. The eighth was less powerful. Matt opened his eyes for the ninth, staring at the LED display of the clock as his ejaculatory pulses tapered off. A few seconds later the flared head of his cock began to recede to its normal proportions and his penis began sliding out of Jennifer as his erection diminished.

They both knew what came next. Matt’s flared cockhead kept every drop of cum deep inside Jennifer for the duration of his ejaculation, but as it shrank back to normal size the seal it created against Jennifer’s winking vaginal walls would fail, and in a singular instant a deluge of cum would squirt from her pussy, usually forcefully enough to soak Matt’s balls.

The LED display changed from 5:39 to 5:40 at the precise moment it happened. The unique fwop-gsssshhh sound of the seal breaking and cum pouring from Jennifer’s pussy onto her bedsheets broke the silence in the room. Matt’s eyes stayed on the clock as his retreating, softening cock inched its way out of his sister.

Matt’s cock was still half-erect when he lifted himself off the small hill that was his sister’s butt. It was done – he got what he came to his sister’s room for, so there was no need to stay. So without a word he rolled over under Jennifer’s sheets, his cum-smeared cock coating her butt and sheets with a wet trail as he crawled off her and out of her bed.

Silently Matt crept out of his sister’s room, leaving her to deal with the mess he’d made. She’d never complained about it, so he didn’t think about it too much. She’d taught him that he didn’t need to worry about the consequences of sex.

He fell back into his own bed and pulled the covers back over himself. 5:41, the glowing red LED display on his clock said. He’d only been gone ten minutes, and it was still nearly an hour before his mom would knock on his door to wake him up for school. Maybe he still had time to catch up on some much-needed sleep before then.

- -

That had been nearly 17 hours ago. Almost as soon as Matt heard his mom call ‘good night’ from the hallway he had his plaid pajama pants off and was stroking his cock again. 

17 hours without sex. It seemed like an eternity in the new sex-drowned reality he found himself in. The 14-year-old shire horse was horny almost constantly. He barely even played video games at all any more – the obsessive part of his brain that video games had appealed to had been taken over and corrupted by sex. It was almost all he thought about any more.

Matt gripped his enormous cock tighter and stroked faster. The lights in the hallway were still on, which meant his mom had gone back downstairs to watch TV instead of to bed. How much longer would she stay up? 30 minutes? An hour? And even then it’d still be another 20 minutes until sex, since he and Jennifer had decided to wait that long after the hallway lights went out, just to be safe.

Matt turned over and looked at the red LED display on his clock. 10:03. How could it have only been three minutes? How could he possibly wait as long as he needed to for his mom to go to sleep?

He turned over again with a whine, laying straight on his back looking up at his ceiling in frustration, the same as he had the night he’d unknowingly sired a foal with his sister. The shaft of his massive black horse cock laid heavily on his slim stomach and slight chest, the flat, unflared head reaching slightly past his nipples and nearly to his neck. He massaged it skillfully – maybe he should finish? If it was going to be an hour before sex he would be able to get it up again. But was it worth it if his mom went to sleep sooner than he thought?

Matt mulled over this decision. He turned over again – the clock read 10:04. That was it, he thought. There was no way he would last an hour or more waiting for his mom to go to sleep, and he was way too horny to be able to fall asleep without getting off.

Matt wrapped his hand around the unflared head of his cock, starting to massage it in the way he knew would get him off in seconds. He closed his eyes and pursed his lips – this wouldn’t take long.

Suddenly Matt’s equine ears pivoted, his eyes shot open.

“Jennifer?” he whispered, eyes jolting open as he held his cock in his hand awkwardly, though he didn’t need an answer to know it was her. The bathroom door had opened and in the dark he saw the almost impossibly tall, thick silhouette of his sister slipped into his room.

She didn’t answer him, as it happened.

“Jennifer! Mom’s still awake! What are you doing?!” Matt whispered forcefully, but by the time he said it his sister had already made her way the short distance to his bed, her hoofsteps muffled by the carpet. She lifted up his sheets like they were her own, sliding next to him under the covers. The bedframe creaked as it adjusted to the extra 350 pounds.

“Shh, shut up… just stay quiet and she won’t hear us…” Jennifer whispered back, shuffling under the covers to get next to her brother.

“Wait…” Matt squeaked. Jennifer was already totally naked. Matt felt her lift her leg over his body, the weight of her thigh effectively pinning him down.

“No. Need it now…” was her whispered reply. Matt felt her fingers wrap around the unflared end of his black horse-cock, the pink splotches hidden in the darkness. It was already rock hard dripping precum, which Matt knew she’d feel immediately. Without any delay or even the hint of the pretense of foreplay, Jennifer guided her little brother’s cock to the dripping wet cleft between her legs.

“Wait!”

Jennifer’s free hand went to her brother’s mouth, muzzling him and cutting him off mid-sentence.

“Shh, Matt! Mom won’t hear anything if you stay quiet,” she whispered in her brother’s ear. At the same time she’d lined his tip up with her puffy, winking horse pussy. “Just shut up and let me ride your cock.”

Any thought of resistance melted away from Matt as Jennifer edged downward and slid backwards, the hot walls of her sex enveloping his thick shaft.

“Oh my god… fuck...” Jennifer whispered, less to Matt than to herself as she lowered herself, inch by inch, onto the object of her obsession.

A sort of strange dichotomy had emerged in the past few week Matt and Jennifer had been having sex. Jennifer had always been the heaviest sleeper, so when they had sex in the morning she tended to adopt a more passive role, letting Matt fuck her however he wanted while she was still half asleep. At night it was the opposite – she almost always took the dominant role, sometimes treating her brother like little more than a fuck toy.

They both knew that Jennifer could always be the dominant one if she wanted to, of course. She could have done what she was doing now months ago, before their relationship changed, and Matt would have been powerless to stop her. That’s how it was when she sat on his chest before heading off to the Halloween party that fateful day, right?

“Yes… oh god, fuck...” she whispered more loudly as her brother hilted her, all 14 inches, so much deeper than any other colt she’d fucked.

She still had her hand over Matt’s mouth as she began to roll her wide, meaty hips. Neither appreciated how silly the gesture was; Matt was the one who was usually quiet during sex. It was Jennifer who couldn’t keep her mouth shut when she fucked.

“Hnnn…” Jennifer grunted, nostrils flaring, her hands darting down underneath Matt’s covers to his hips. Without any real sign of exertion she lifted his lower body off the mattress, pulling him up to her as she shuffled backwards on her knees. When she’d crept into Matt’s bed his head had been on his pillow, so to get ‘aligned’ with him in the way that really mattered she’d had to keep her own body raised up off the bed. The only way she’d be able to lay flat while riding her brother’s cock was for him to be a lot closer to the foot of the bed.

Matt felt himself being pulled underneath the sheets of his own bed, his sister’s strong hands wrapped around his waist and in control of his body. The covers retreated over his head. The moment he stopped being dragged towards the foot of the bed Jennifer let her body down onto his, pressing him into his mattress.

Suddenly, as she lowered her body down onto him, Matt’s sister’s huge breasts were straddling his head. Such was their size difference that his face only came to his sister’s chest when their bodies were pressed together. Jennifer’s own face was on her brother’s pillow while her body pushed him into the bed. Her hips were now bucking forcefully enough that Matt’s entire bed had started rocking, the frame squeaking in regular intervals.

“Fuck yes… fuck… fuck my pussy...”

Jennifer’s voice was above a whisper now. She was still trying to restrain herself but was rapidly losing control. Bouncing on this cock had been all she’d been able to think about all day.

“Deep, baby… yes, just like that…”

Matt’s thoughts were no longer on how much noise Jennifer was making, though they really should have been – between her words and her humping she was getting louder every second. His hands gripped her immense hips, her short equine hair making her skin feel like warm velvet. Matt was pulling down and thrusting up into her every time she bucked.

“Yes… taste it…”

Jennifer had lifted herself up slightly, which Matt took as an invitation to start sucking on her soft black nipple. His thick, almost prehensile horse lips latched firmly onto her bare black skin. She was bouncing hard enough now that the slaps of their gray-furred skin and the wet, sloppy sounds of the sex itself was almost as loud as the squeaking of the bed.

For several minutes she rode her brother’s cock, varying the speed and the angle to suit her pleasure. She felt his little hands feeling up and down her body the whole while. She never told him, but she loved the way he felt her up when they were having sex. Even if it was her dorky little brother, there was someone in the world that really wanted her for more than just a one-time fling. That was the interpretation she chose to go with, anyway.

Jennifer felt Matt’s hand slip off from her waist. He started tugging on the sheets from underneath.

She stopped bucking, sitting heavily down on her brother, all 14 inches of his cock deep inside her. She crooned her neck down, her long equine snout parting the sheets.

“It’s too stuffy. I need some air,” Matt said, haltingly. It hadn’t been his intent for Jennifer to stop riding him.

“Oh my fucking god Matt you’re such a spoiled little baby! You’re getting more pussy than any middle-school kid in history and you’re whining about something so stupid…”

“I wasn’t whining! I just needed to get some air! I didn’t say to stop!”

It was the kind of banter common to siblings, arguing about trivialities and quick to blame each other for any wrong, real or imagined. Their situation may have changed in the past few weeks, but Jennifer was still Matt’s bossy older sister, and Matt was still her dorky little brother.

“Oh, so it my fault now? Was I smothering you?” Jennifer teased, simultaneously lowering her massive 8-foot frame on top of her brother, her full weight bearing down on him with all 14 inches of his cock still deep inside her. She was always careful not to put too much weight on him when they were in bed, knowing that if she did she really could hurt him.

She felt her relatively tiny brother squirm underneath her for a few seconds before lifting herself back up.

“Jennifer! Come on, that’s not funny!” Matt exhaled in a way that Jennifer felt was over-exaggerated, almost to the point of being theatrical. 

“Oh, you ‘come on.’ I think it’s pretty funny. We’re both pretty funny…” Jennifer said as she started rolling her hips again, now in a kind of circular motion on the horse-cock that filled her. She leaned down again, letting her boobs straddle Matt’s head once more.

“Come on, baby… come on…” she whispered as she started bucking on Matt again.

“Still… too stuffy…” came his muffled reply.

“Oh, my, fucking, god Matt you’re such a spoiled fucking baby!”

Jennifer grabbed onto the blanket and sheets, pulling them off the bed and throwing them down onto the floor.

“Hey! Now I have to make the bed!”

“Oh my god you’re still whining. I thought you needed some air?”

“Well yeah, but...”

“Maybe you just need more air. Maybe your big sister is smothering you after all…” Jennifer said with a smirk. She lifted herself up off her brother, letting his slick shaft slide entirely out of her.

Matt’s room was dark, but enough light filtered in under his door from the hallway that he was able to see Jennifer as she stepped off the bed.

“W-wait! I didn’t mean stop!” he begged.

“I’m not gonna stop, idiot…” Jennifer replied, as if her brother even suggesting she might were ridiculous.

Matt watched as she turned around so that she was facing away from him, her huge equine butt in front of his face. She lifted her leg back up and over him, planting her knee on the bed on the far side of Matt’s body.

“Just changing position. So I can ride your cock without having to listen to you whine,” she said without looking back at him.

Jennifer edged back further, her immense butt resting lightly on Matt’s chest. He couldn’t help being reminded of the same view he had just a month and a half ago, when Jennifer barged into his bedroom before the Halloween party, ‘borrowed’ twenty dollars, ruined his game and sat on him. Even as she bullied him then, he had been mesmerized by the sight of her exposed equine pussy and protruding donut-like tailhole peeking from under the towel she was wearing. If she had waited a few more seconds to lift herself off of him then, Matt had no doubt he would have reached outto feel her, even though it would have surely meant the beating of his life. What would his excuse have been?

But he needed no excuse now. There was no resistance as his hands lustfully roamed across the massive tract of dappled gray that was his sister’s ass, no hint that she was anything but eager as those hands converged where the short fur ceased and skin turned from gray to black. The signs of Jennifer’s arousal were unmistakable, involuntary actions her body was taking to telegraph her desire to be bred and provide easy access to her mate – her tail was lifted so high that it actually curved back towards her back, and her dripping-wet horse pussy winked as Matt spread it slightly with his thumbs.

Without thinking Matt closed his eyes and opened his mouth. His tongue found its way between his sister’s puffy black nether lips. He tasted her as he licked upwards, past her slit towards her tail. He didn’t pause as his tongue first met the convex rim of her massive donut, then traced around the rim in a circular motion.

“Oh my god Matt, don’t… that’s my butthole you idiot. That’s super fucking gross,” Jennifer said.

Matt pressed his face forward into his sister’s butt. His lips latched around the rim of Jennifer’s tailhole, sucking gently on her puckered donut and exploring it with his tongue, first around the rim and over the ridge, then a timid prod into the center.

“Nasty little pervert… that’s not my… fuck…” Jennifer sighed, feeling her brother’s tongue slip into her. She’d never even thought about what it would feel like to have her tailhole played with. If Matt had asked if he could do it five minutes ago she would have been disgusted, but she wasn’t offering any resistance now that he was doing it. If anything she was pressing her mammoth butt back into him.

Matt sucked harder, pulling his sister’s equine donut into his mouth for a moment before letting go with a loud kissing sound. For a moment there was silence, and Matt started leaning forward again, but Jennifer regained her composure before he had the chance to kiss her tailhole once more.

“We are not making out tonight,” she said in a tone meant to be more serious than it came out as her hips drifted forward away from Matt’s mouth. “Don’t even fucking try. Keep your mouth away from me after that, little weirdo.”

Jennifer wrapped her fingers around the end of her brother’s cock, guiding it again where it belonged, right between her legs and into her waiting, winking sex. Smoothly she lowered herself down on it once more, not realizing the absurdity of considering being rimmed by her little brother to be ‘weird’ while thinking nothing of riding his raw cock and taking his load.

She felt Matt’s hands grip her legs just above her back-curved equine ankles as she started bouncing on his cock once again. Maybe he was a little weirdo, maybe he was her brother and maybe she was letting him get away with more than she should, but this was still by far the best dick she’d ever had in her life. If she had to occasionally endure having her butthole licked or whatever other weird little sexual kinks Matt might be into, it was worth it so long as she had his cock on demand. Deep down she knew that she’d do almost anything Matt asked her to if he ever threatened to withhold sex from her, but he didn’t need to know that.

“There we go baby… there we go…” she said in the hoarse, needy voice Matt had grown accustomed to whenever they fucked. She was riding him harder now, and Matt knew he wouldn’t be able to hold out long if she kept up this pace.

Jennifer was having trouble maintaining that pace in the position she was in, though – her legs were awkwardly pressed against the headboard of Matt’s bed. If she could just get more leverage, she thought.

“Hey, what are doing…” Matt started as Jennifer grabbed his ankles.

“Shut up,” she whispered almost to herself as she shuffled on her knees to the corner of Matt’s bed, effortlessly dragging him with her across the sheets, keeping him between her legs, greedily keeping his cock inside her. “Don’t move. Just sit here.”

Matt figured out what she was doing only after he found his legs dangling off the side of the bed. She lifted him slightly as she raised one of her muscular legs, then the other, planting her hooves on his bedroom floor.

“Are you gonna...” Matt breathed. 

“Just shut up and sit still...”

Jennifer didn’t waste a moment, lowering her hips down onto her brother’s lap and taking the entire length of his cock inside her to the hilt. She was now essentially squatting over Matt, riding him with her hooves on his carpeted floor and butt driving down onto him like a pistoning steam-hammer.

But after just a few moments of heavy humping her thighs were burning. Trying to find a way to take pressure off her legs she bent over, placing her hands on the floor along with her hooves. For a few seconds she tried riding Matt this way, on all fours and humping back into him like a wild animal, but this position was even more uncomfortable than the last.

“Hold on, this isn’t working,” she said, bending further down. “Let me just…”

She bent her knee, lifting one leg up and kicking it sideways before lowering it back on the bed.

“Hey… hey, oww…” she heard Matt squeak. She’d inadvertently pinned Matt’s arm down with her leg, trapping it between her thigh and the bed.

“Oh my god Matt, is it really that hard to move out of the way?” 

“It is when your big dumb leg is bigger than I am…”

Jennifer’s brows furrowed. Her nostrils flared slightly and she opened her mouth to snap something back at her brother like she had so many times in the past. But that feeling passed almost instantly. That wasn’t their relationship any more, and it seemed kind of silly to start petty sibling bickering with her brother when he was still balls deep inside her.

“Just… grab onto my butt or something, dork,” she said back to him, taking weight off his arm so he could pull it free. 

Matt saw no reason not to do exactly as he was told; Jennifer felt him grip her meaty haunch while she lifted her other leg up from the floor and back onto the bed.

“There we go… that works better.”

This was a new position for both of them, a kind of seated wheelbarrow with Matt sitting on the edge of his bed and Jennifer face down on the floor, her thick ass up and filling the young colt’s lap. Jennifer started rolling her hips sensually, slowly, side-to-side and in a smooth circular motion. There was no need for powerful thrusts in this position – her brother’s entire length was already inside her. She could feel the heat from his massive balls on her stomach below her navel. She had complete control as well, since the weight of her butt and legs alone was enough to keep Matt in place.

“My ‘big dumb leg,’ huh? You like my big dumb legs, though…” Jennifer teased, gently squeezing her brother between them. Her head was down on the carpet, just a few feet away from Matt’s bedroom door. She squinted – she was at eye-level with the sliver of light seeping from the hallway outside her brother’s room, and her eyes were adjusted to the darkness.

“And my big dumb butt, you like that even better… yeah you do, you can’t keep your hands off,” Jennifer said as she lifted her hips a bit. A few inches of her brother’s shaft, slick with their combined juices, slid out of her. Playfully she batted her raised equine tail across Matt’s face, letting the long black hair trail across his cheek and nose.

She lowered herself again, taking her brother to the hilt once more. His long, veiny horse-cock felt so good in this position, wedged as deep inside her as was possible, that Jennifer was getting close to climaxing just from the feeling of her brother filling her. From the way Matt was squirming underneath her she thought he was too.

The only part of herself she was moving now was her hips, little dips and swirls and slow pushes back into Matt, taking every millimeter he had but still begging for more.

“But that’s not what you like best of all, is it baby…” she said.

“Jennifer….” Matt winced. She could tell he was close.

“This is what you love best of all, yeah baby? Your sister’s big, dumb, wet pussyyy…” she said, drawing out the last syllable as she raised her tail and arched her back. Her hips were still only barely moving, side-to-side now, but as she approached orgasm  her teardrop-shaped horse pussy was winking uncontrollably. With each wink she clenched around Matt’s cock.

“Jenn… nnhh-fff…”

“Tell me you love it.”

“I love it…” Matt answered obediently, voice cracking.

“What do you love, baby?” Jennifer said, louder than she intended.

“I love… your pussy… fuck…”

Matt was gripping his sister’s butt tightly now. The short silvery-gray hair on her flanks bunched between his fingers and his thumbs reached past where her fur gave way to the bare black skin of her pussy lips. He could feel her butt tense with every wink.

“Yeah? You love it, baby? You love my big dumb pussy? Tell…”

“I’m gonna… gonna cum…!!”

Jennifer’s nostrils flared, her lips snarling with pure lust. Matt normally didn’t say he was about to cum, he just did it. Hearing him say it drove her wild. She drove her hips back into Matt.

“Cum for me, baby! Fucking cum inside me! Fucking fill my big dumb pussy with…”

**knock knock knock!**

“Matt?”

Both siblings froze. For a moment time seemed to freeze with them. This couldn’t be happening.

It was their mom. It was their mom in the hallway knocking on Matt’s bedroom door.

She must have heard them.

“Matt? Are you still awake?”

Seconds ticked like hours on the red LED clock radio on Matt’s nightstand. Should he answer? Stay silent?

The doorknob jiggled, metallic clinking. Locked.

“Yes ma’am, I’m awake…” Matt heard himself answering to his mom, spooked into a reply when she tried to open the door.

As he exhaled the breath he’d been holding, he also realized he was still balls-deep in Jennifer, a hair-trigger away from cumming. The dumb, reptile part of his brain was screaming at him to finish.

Jennifer, for her part, was still holding her breath. She’d opened her eyes again, seeing the two dim spots in the light shining under the door, shadows cast by her mother’s hooves as she stood feet away. But that dumb, reptile part of her brain was in the same state as Matt’s…

“I know what you’re doing in there, young man...”

A bolt of electric panic snaked through both Matt and Jennifer in the brief moment before their mom continued.

“I know you’re playing your video games after bedtime.”

Jennifer finally exhaled, a flood of relief washing over her. Her body and mind simultaneously felt the release of tension and forced her attention back on the hard horse cock buried deep inside her, aching for release.

“S-sorry Mom, I… I…”

Matt’s eyes widened, his hands clamped tightly onto Jennifer’s butt. He couldn’t believe this was happening. They were both remaining still, but his big dumb sister’s big, dumb pussy was still winking, squeezing his cock every few seconds. There was no way he could hold out.

“This is the last time, Matt. Next time I catch you playing that Pretendo after bedtime we’re going to move it back to the living room. Understood?”

Jennifer felt her brother’s feeble, desperate attempt to push her butt off him in a last ditch effort not to creampie his sister while talking to their mom, but with 350 pounds of horny teenage draft horse on his lap he had no chance. After only a second or two she felt him clamp his hands down on her ass again, and she knew he was about to cum.

“Matt? Do we understand? Answer me, young man, or I’m coming in!”

“Mom, no, don’t… don’t come in… inside… don’t cum inside…!!”

Matt’s eyes rolled back, his jaw slacked, his tongue lolled out of his mouth. The bulbous head of his 14-inch horse-cock flared.

Jennifer buried her face in the crook of her elbow, hoping to muffle the moan she couldn’t hold back. She went over the edge the instant she felt Matt’s flare widening deep inside her, spreading her tight, muscular walls. Involuntarily she clamped hard as they came in unison.

She could feel the rigid pulsation from Matt’s thick black shaft as the first powerful gush of cum flooded her. She could almost hear herself being filled; they were both still trying to remain as still and quiet as possible, so for the first time her focus was solely on the mechanical process of being inseminated, pulse after pulse of hot cum injected into her waiting womb.

“So do we understand? No Pretendo after 10 o’clock or I take it away.”

“Yes… yes… yes ma’am,” Matt exhaled, coming down from his orgasm, the last few spurting ejaculatory pulses trailing off as he answered his mom. Jennifer was covering her mouth with both hands now and her legs were trembling – Matt could tell she was still cumming hard.

“Yes ma’am what?”

“Yes ma’am, no Pretendo after bedtime,” Matt answered, trying his hardest to sound as normal as he could. He leaned forward, his arms sliding across Jennifer’s bare haunches up to the small of her back.

“Or else what?”

“Or else you’ll take it back downstairs.”

“And don’t you forget it. Final warning,” Matt’s mom replied, just feet away from her children’s incestuous coupling on the other side of the door. “I’m going to take a shower. If you’re still playing video games when I get out I’m taking it right now. Understood?”

“Okay mom,” Matt said. Jennifer had stopped trembling, but Matt could hear her breathing hard.

“Okay what?”

“Okay I’ll go to sleep now and I won’t play Pretendo after bedtime any more.”

“You got yourself a deal,” Matt’s mom said playfully after a short pause. “Good night sweetie, love you.”

“Good night mom, love you too,” Matt answered as if everything were normal, as if he hadn’t just dumped half a liter of cum into his mom’s precious daughter.

They remained still and silent, not daring to move a muscle until the light shining in from underneath the door disappeared. Even after they were sure their mom was gone it took half a minute before either of them said a word.

“Shouldn’t be playing those games past your bedtime, young man,” Jennifer finally quipped with a smirk. She lifted her hips off her brother and slid forward. Matt’s now semi-flaccid dick flopped out of her as she did, and with it the familiar cascade of cum. It splattered onto Matt’s bed and dripped onto his carpet as Jennifer hopped off him and stood up.

“You’re the one making all the noise, bouncing on my bed and hitting the board against the wall and everything else, and we’re lucky…”

“You’re lucky. Lucky I’m letting you get lucky,” Jennifer replied dismissively.

“What… what the heck are you talking about? Do you not get how close we got to mom catching us? What if the door wasn’t locked?”

Jennifer was well aware of just how close their mom was to catching them, of course – but she wasn’t about to let her dopey little brother have the last word. It was always more fun to leave him confused and befuddled.

“Good night, lucky boy,” she lilted as she left his room, heading back to hers through the bathroom they shared, cum dribbling down her legs. “Don’t let mom catch you playing games…”

- - 

It was still dark when Matt woke up. He rolled over, opening one eye just enough to see what time was displayed on the red LED of his clock radio.

“Nnnggh…” he grunted. 5:34.

It was probably close to 2 a.m. when he finally fell asleep, as best as he could figure. After almost getting caught by his mom the night before he couldn’t quiet his mind for hours, despite how desperately tired he was from what could best be described, at this point, as chronic sleep deprivation. For the past few weeks he’d stayed up late and woken up early every single day to have sex with his sister, and it was starting to wear him down.

For a moment he considered getting out of bed, creeping into Jennifer’s room, crawling under her sheets, mounting her, breeding her. She’d let him. Any time, she’d let him. There was a willing, stunningly gorgeous mare in the other room and all he had to do was get out of bed. What he wouldn’t have given for this chance just a few weeks ago. His morning wood wasn’t going to take care of itself.

But he was so tired, and his bed was so warm and cozy. Let’s not do it this morning, he thought. Let’s just get some sleep instead, like I used to…

He was half asleep when he heard the door to the bathroom creak open. The red LED displayed 5:49.

“J-Jenn…”

“Shh,” she whispered, “don’t say anything.”

She carefully lifted the covers on Matt’s bed, sliding underneath the sheets. Matt could feel from her warmth that she was totally naked. She straddled him, aligning herself to him, and Matt’s hands instinctively went to her hips.

“Just let me ride you, baby. I’ll be quiet…” she whispered as Matt’s cock slid inside her.