Camping Trip For one weekend every January, my sisters and I would make a trip back to Minnesota, heading to a remote part of the state, somewhere up in the Iron Range. We always chose a spot that was several miles from any nearby towns, trying to keep to ourselves as much as possible. There were a couple reasons why we did this every year. For one, Charlene and I got a little homesick once in a while and we wanted to pay a visit to our home state. However, the other reason why we did this was so that I could help my sisters realize their full potential. Out of the three of us, I was the only one who was able to change into a ninetales, neither Charlene nor Eva could do so...even though Eva had a nine-tailed eevee form like I did. I figured that if we spent some time in the cold north woods in our fire fox forms that they would eventually gain enough experience to become ninetales. This year, the set-up for the trip couldn't have been any better. We arrived in the north woods around the time that a fresh Arctic air mass was moving in. The air temperature was already down to -15 and was continuing to drop. For most, temperatures this cold would force even those who were native to the region to not want to go out unless they had to. For the three of us, however, it didn't bother us at all. A quick transformation into our "fire fox" forms was all it took to keep warm. As a ninetales, I was able to go around wearing a t-shirt and shorts while my sisters each wore a bikini, with Charlene's being all-purple and Eva's being dark blue with pink flower patterns on them. Although we could easily keep ourselves warm by using our natural fire fox heat, there were other challenges that were presented to us by camping outdoors in the middle of a Minnesota winter. Inside the rental truck we had, there were two coolers, one of them was filled with meat and the other was filled with various drinks. We could leave the meat cooler in the cold without too much of a problem, since the meat inside was already frozen and we could easily thaw it out when we wanted to eat. However, the beverage cooler needed to stay warm enough to keep the drinks inside of it from freezing. Fortunately, we had a solution to that. We had our own "Personal Greenhouse Device" with us, a device that would create an invisible energy dome that was 20 feet high by 40 feet in diameter. The air inside the dome would be heated to a comfortable 68 degrees, maintaining that temperature while the device was activated. Of course, the dome needed bare ground to be set on first and as we got out of the truck, my sisters and I stepped in snow that was about 8 inches deep. To solve the problem, my sisters and I picked out a spot that was open, far enough from the tree line to avoid setting an accidental forest fire and then the three of us opened our mouths together, blasting flames onto the snowpack in front of us. The snow rapidly melted thanks to our combined heat, getting down to the bare ground underneath within just a couple of minutes. As we were busy melting the snow, I started to notice that Eva's body fur was changing color. It was going from the traditional orange color of a vulpix to gold/white tone. Furthermore, her tails became longer, also changing color as more of them appeared. It didn't take long for me to figure out what was happening...Eva was becoming a ninetales and she didn't notice it yet, neither did Charlene. After we melted down enough of the snow, the three of us stopped using our flames and took a moment to catch our breath. Sustaining a flame for that long took a lot of effort, especially for Charlene. Eva and I were able to recover much quicker, which is when I approached my younger sister and placed my hand gently on her cheek. "Have you looked at yourself yet, Eva?", I asked curiously, trying to get her to discover what happened. Eva seemed a bit confused at first, but then took a look at her arms, noticing the change in her body fur. "Hey, wait a minute...why is my fur different?", she asked curiously before going over to the truck and peeking into one of the side rear-view mirrors. That was when she realized she had become a ninetales. "Oh my God! It finally happened!", Eva exclaimed gleefully, putting her hands to her cheeks, even going as far as to pinching them to make sure she wasn't dreaming. After she did this, Eva was convinced that she was able to become a Ninetales now and then let out a soft and seductive murr before turning towards me. "You know what this means, don't you?", Eva asked playfully, having a twinkle in her blue eyes while a puff of smoke came out of her nose, one that formed into a heart with an arrow shot through it. She soon embraced me, licking the side of my neck very slowly with her hot tongue, pressing her body against my own as I couldn't help getting turned on by Eva's behavior. Inside my shorts, my foxhood rapidly grew erect, throbbing for Eva's warmth while trickling precum from the tip. My testicles felt heavy and churned with life, getting ready to give Eva what I promised her the day she became a ninetales. Years earlier, when Charlene and I first discovered we had a younger sister and Eva found out that I could become a ninetales, both of my sisters wanted me to help them 'train'. Later, I found out that Eva and Charlene both wanted me to impregnate them with vulpix pups of their own. The only way that I could guarantee this happening would be if I mated with them while we were both in ninetales form. This led me to make a deal with Eva and Charlene. I promised that I would impregnate them while I was in ninetales form, but not until they were able to change into a ninetales themselves. Now that Eva was able to do so, it appeared that she wanted me to keep the promise I made. "Did you take any yiffberries before we left, Eva?", I asked curiously, wondering if Eva was receptive now or if we'd have to wait. Her eyes opened wide and she suddenly released me, grumbling a bit. "Dammit! Why did I decide to take those this morning? Now it'll be two days before I can get pregnant!", Eva exclaimed, lamenting the fact that she decided to 'play it safe' instead of letting things happen naturally. I understood Eva's frustration, but there was nothing she could do about it. She simply had to wait for the chemicals in the yiffberries she took to run their course so that she would be able to ovulate once again. In the meantime, I held onto Eva and nuzzled against her, intentionally letting the bulge in my shorts touch against the bottom of her bikini. She soon murred and rubbed against me slowly. "Patience Eva, you'll get your pups soon enough", I coaxed, assuring Eva that I would make her pregnant before we went back to Familia. Meanwhile, Charlene finally recovered enough from using her flame with ours to melt the snow to realize what was going on. She saw Eva and I embracing, both of us in our ninetales forms while she was still a vulpix. "It's not fair, dammit! How the hell is she able to change before I am?", Charlene grumbled, a bit jealous that Eva became a ninetales before she did, especially considering that Charlene was three years older than Eva. I heard Charlene's comment and I felt bad for her. After all, she was my twin sister and she figured that she should've been able to change into a ninetales by now. I didn't like seeing Charlene upset, so I thought of an idea to make her feel better, though I would need Eva's co-operation. "Eva, what do you say we give Charlene a 'special' training session", I suggested to Eva in a soft and playful manner, hoping that Eva would get the message. Eva kept nuzzling against me while continuing to rub her crotch against my bulge. "What did you have in mind?", Eva asked curiously, wanting to know more about the idea. I suggested that we could have a threesome. She and Charlene could trib together while I let Charlene give oral sex to me, then Charlene could give oral sex to Eva while I mounted Charlene from behind. Although, I wasn't sure how Eva would take that idea, since I assumed she wanted me inside her now. "I'll do it...under one condition", Eva mentioned as I looked at her and asked what the condition was. "If Charlene becomes a ninetales as a result of this 'training' session, I want you to promise that you'll impregnate me first. I also want you to abstain from having sex until I'm receptive again after this, OK?", Eva soon asked, determined to have vulpix pups from my seed. I figured it would be fair to impregnate Eva first. After all, she was the first to change, so she should be the first to have pups. The abstaining from sex part would be more difficult, though. Being with both my sisters at the same time was sure to arouse me sexually and it might be a challenge for me to ignore my own biological urges. "Can I at least masturbate if I feel the urge hit me?", I asked, not certain if I could resist for two days. Eva gave it a little more thought and came up with an answer. "Alright, you can masturbate if you need to...but no vaginal sex after this. Also, I want you to start taking blue kaorin berries tomorrow. I want to make sure you have lots of seed for me when we breed", Eva explained. Eva knew that I had a bottle containing freeze-dried blue kaorin berries in it. The berries were a known Raposian fertility drug and increased sperm production in males while inducing ovulation in females (or increasing the number of eggs released if she was already receptive). I never had a use for them before, but I figured Eva would feel better if I had more sperm to give her when we mated. I agreed to Eva's condition and the two of us went over to Charlene to try and make her feel better. I placed my arm around Charlene while Eva came along to her other side, also putting her arm around our sister. "Come with us, Sis. Eva and I are going to help you", I told Charlene as she looked at me curiously as we all started walking away from the campsite, looking for a nice open area in the woods. It appeared that Charlene wasn't exactly sure what to think about all of this. After all, it wasn't the first time we were sexually engaged with her while she was in vulpix form and she never changed previously. Still, it seemed that Charlene was willing to give it a try and went along with us. Perhaps getting to do it with two ninetales siblings would finally give her the experience she needed to catch up to us. We wandered through the snow for a few minutes, with me stopping for a few seconds every 50 feet or so to scratch a crude arrow into the bark of a nearby tree with one of my claws, making sure that the three of us could find our way back to our campsite when we were done. Then, after walking for about 1/5 of a mile, the three of us arrived in another open area in the woods...although this area wasn't unoccupied at the time. Near the edge of the opening on the other side, a pair of non-anthro red foxes were in the middle of starting a family of their own. They were joined together in the traditional vulpine tie, with the male slowly inseminating the vixen. The two foxes heard us coming which caused the male to gekker and holler as if he were saying "Hey buddy, this is our spot! Go find your own!" Naturally, I was a tad annoyed by the male fox's attitude. Part of me wanted to show him who was boss by letting out a much louder growl and a bit of flame. However, I decided against it because his mate responded for me. She yapped back at him as if she were saying "hey, shut up! They're not bothering us! Besides, I think I saw smoke coming out of the male's nose, so it's probably best that we don't mess with them". After being rebuked by the future mother of his pups, the male fox wisely calmed down and focused on passing his seed to his vixen. Deciding that it would be better just to ignore the three of us since he'd probably live longer that way. I had no intention of hurting either of them, though I would've scared them off with the flames and growling if the vixen hadn't provided her mate with some common sense. Besides, if I really wanted to piss the male off, I'd change into my non-anthro ninetales form after he was done mating with the vixen, mount her and pass my seed onto her eggs. However, I had no intention of doing that to him. As far as I was concerned he could have her, I was more interested in spending time with my sisters. As soon as that incident seemed to be under control, I slipped out of my clothes, letting them drop to the snow-covered ground below. The thought of spending time with Charlene and Eva helped me keep the erection, which stood straight up and dribbled with hot precum onto the snow below. When it landed, small amounts of steam rose from the snowpack as the heat from my juices ate away at the snow as if acid were poured on it. In my ninetales form, my erection stood at 12 inches in length and my knot was also bigger. It also had some other tricks that I could perform during mating, but I would have to put it inside a female (or Sapphire) in order for these tricks to be used. I took a moment to stretch, allowing my hot and horny foxhood to twitch in the chilly air, all while it kept throbbing for my sisters. At the same time, Charlene and Eva both removed their bikinis, no doubt turned on by the 12 inches of my maleness being so close to them. None of us knew the reason why the length and thickness of my shaft could change depending on what form I took, but I didn't think my sisters would mind that much. They didn't get to play with my ninetales form that much and the extra length on my shaft would be an added bonus for them. Although, it also seemed as if the length of their vaginal canals also changed when they assumed certain forms. Even with my shaft at its current length and even when I had my knot inside them, the tip of my shaft would just barely kiss against their cervixes when we had sex. A few moments later, once all three of us were naked, Charlene looked at me with her six tails raised high behind her back, seeming a bit curious. "So...what did you have planned for me?", Charlene soon asked, wondering what we were going to do with her. Eva came over to Charlene placing a hand down around her vaginal folds, rubbing them lightly and making my twin sister pant a little as a bit of smoke escaped her mouth. "Well, for starters, we thought that you and I could rub our hot pussies together for a bit. You know, to help get excited for when he puts that in there", Eva commented in a playful manner, pointing to me and my erection. Charlene continued to feel Eva's hand against her warm crotch and felt excited by the touching. She liked the idea of tribbing with her, and the idea of having sex with me afterward. However, there was something Charlene had in mind. "OK...but what about him? What is he going to do while we're 'kissing'?", Charlene asked. I knew why Charlene asked this, she didn't like leaving me out of moments like this when I was around. "Well, that's up to you, Sis. You see, Eva and I thought that while you two are doing that, you could help me with this", I mentioned. "I know you generally don't like giving oral sex to me, unless I'm in raposa form, that's why I'm going to leave it up to you to decide. Otherwise, I can just watch the two of you trib and masturbate until you're ready", I commented, letting Charlene decide for herself what she wanted. Charlene soon asked Eva if she could stop touching her for a moment so she could speak to me alone and Eva did as Charlene asked. That allowed Charlene to come over to me, placing her arms around my upper body and making sure that the warmth of her vulpix folds kissed against the underside of my throbbing length. "I never said that I didn't like giving oral sex to you. It's just that I prefer to do it when you're in raposa form because I like the flavor of your seed in that form. It tastes an awful lot like cashews, and I don't think I need to tell you how much I like eating them", Charlene mentioned as I blushed a little and nuzzled against her softly. "I know Sis...I like eating cashews too", I mentioned sweetly. As we nuzzled, Charlene kept grinding her warmth against my shaft, making it dribble with precum even more and leaving more melted spots in the snowpack from where it came into contact with the frozen ground. "Besides, you know that I like it the most when I feel your cream hit the inside of my womb. It's one of my favorite parts of having sex with you...well, that and getting to be stuck to you for a long time while you slowly fill me", Charlene soon added, murring sweetly, suggesting that she wanted me to turn the tie with her, which came as no surprise to me. I gave my twin sister a kiss on her lips and embraced her tightly. "Charlene, trust me...I'll be more than happy to turn the tie with you when we have sex", I assured Charlene before she murred and nuzzled me a little more before coming up with a decision. "Hey...I have an idea. Why don't I help you with that while Eva and I trib and then you can shoot it inside her. Then, while you're having sex with me, I'll eat out the creampie you give to Eva", Charlene suggested. I had no problem with Charlene's suggestion in theory, but I'd have to make sure that I didn't go off until I got it into Eva's vaginal canal. "Well, we could try...but I don't know how long I'll be able to hold it in once I'm ready to blow", I answered back while Eva overheard the two of us talking. By now, the other two foxes had finished mating and ran off, leaving the three of us alone to do our business. Eva came up from behind me, licked the side of my neck and then nuzzled me gently, all while her hands rested on my belly and I felt her own vaginal lips kissing against a couple of my tails. "I can go along with that. In fact, I like the thought of getting to feel you cum inside me while we play", Eva mentioned happily as I felt both of my sisters pressing their warm bodies against mine, causing me to feel hot and very excited. In fact, I grew so aroused that my precum was now launching from my tip in spurts, hitting against Charlene's belly. "Charlene, Eva, as much as I like having you two this close to me, you're both making me feel really horny right now. Perhaps we should get started with our 'training session' before you make me go off too soon", I mentioned, already feeling a strong churning within my testicles, being spurred on by the closeness of my sisters. Charlene seemed more than eager to get started, with Eva not far behind as they both kissed me on my cheeks briefly and then got into position on the snow. I watched as Charlene and Eva both opened their legs wide as Eva moved in closer to my twin sister. As they were getting ready to start rubbing against each other, I dropped down to my knees and moved in close enough to Charlene so my throbbing foxhood could be within reach of her mouth. The tip of my length continued to spurt with hot precum, some of it landing on Charlene's face and upper chest while other spurts landed in the snow, creating melted spots in the snowpack wherever it landed. Charlene decided to move a little closer to me and reach out towards my shaft with her tongue, touching it against the underside around the knot. From there, I felt her lick it upward slowly, heading towards the tip while Eva grabbed hold of one of Charlene's legs. By now, Eva's hot and fresh ninetales pussy was dripping wet, leaving melted spots in the snow from where her nectar contacted the snowpack. Eva knew she would have to be the one to lead in this case, since Charlene was going to be busy playing with me. However, Eva didn't mind taking the lead this time around. It would be a welcome change of pace for her since Charlene was usually the one who was dominant in their relationship. I started to pant a bit when Charlene was licking my shaft, now going along the topside of it after she reached the tip, with her blue eyes staring back at me. Her hot tongue continued to coax precum out of me, launching it towards her face and getting on her cheeks, hair, and a bit onto her neck. Then, Eva's pussy lips contacted Charlene's, with Eva holding onto Charlene's leg tightly to make sure she had good contact with her. This made Charlene yip briefly from the contact of a hot ninetales vagina against her vulpix folds, but she soon started to murr and reach out for my length, grabbing it around the knot. Soon after, Charlene took my length into her mouth, taking about half of it inside while using her tongue to cradle my shaft from underneath. The inside of her mouth felt hot and very moist, causing my maleness to pulse against her tongue while my precum kept spurting from it. Her hand grasped my knot, holding it tight enough to make it easy to keep it from popping out while she sucked on it. I panted more when I felt Charlene moving back and forth along my foxhood, feeling smoke and a bit of flame escape my nose as she gave me oral pleasure, all while watching Eva grinding against Charlene's pussy with her own. While Charlene was giving me head, I felt vibrations in her mouth from the murring she was doing, murring because of what she felt from Eva. The contact of their pussies caused heat to radiate around the two of them, melting the snow within a couple of feet of where they came into contact. The snow directly underneath Charlene and Eva was also melting from their body heat, melting all the way down to the ground underneath. While Eva squished her pussy against Charlene's, I noticed that she was starting to let out a bit of smoke and flame from her nose. "Mmm...yeah...how does that feel, Charlene? Am I hot enough for you?", Eva commented in a playful manner, doing so while murring and moaning from sexual pleasure, holding Charlene's leg tightly and grinding against her big sister harder and a bit faster. I heard a long and loud moan come from Charlene while she was busy sucking on my maleness, undoubtedly enjoying what she felt down around her vixen folds. During this time, I began to notice that the six tails that Charlene had in her vulpix form were beginning to glow a bit. As this happened, Charlene suddenly tightened her grip around my knot and sucked on my maleness faster, massaging it with her tongue and 'cooking' it with the intense heat that came from inside her throat. My maleness thickened against Charlene's mouth, growing more sensitive to touch as I sensed a fresh load of semen mixing within me. The jets of precum that were produced from my tip came out more frequently and reached deeper into Charlene's oral cavity, sliding down that throat of hers. The way it felt tempted me to keep my pole inside Charlene's mouth until I climaxed, letting her feel my 'hot lava' erupt from the tip and giving her a surprise. However, I knew Charlene rarely swallowed semen, and she usually did it when it was mixed with vaginal juices. Charlene's breath seemed to get hotter the more she sucked on my maleness, adding to the pleasure she was giving me, causing me to pant constantly while my tails were raised high behind my back. I knew it wouldn't be too much longer before I came, and I needed to get Charlene to stop before she really did make me cum inside her mouth. "Ahh...Sis...you're gonna make me cum if you keep doing that!", I exclaimed, letting her know that I was about ready to blow. When she heard this, Charlene immediately stopped what she was doing and released her grip on my poll, also backing away from Eva's crotch. "Well, hurry up and put it in Eva! I don't want to have to rub snow all over me to wash your cum off my body and facial fur!", Charlene responded, letting me know that she only wanted my seed inside her womb, not in her mouth or on her body. I grabbed hold of my maleness between the tip and knot, squeezing it firmly while Eva opened her legs wide to me. "Go ahead and shoot it in me, big brother! Give me a little sample of what it'll feel like when you breed me", Eva gleefully coaxed, eager to accept my seed in her passage. I quickly positioned my shaft against Eva's vaginal opening, pushing it into her canal as I released my grip on it and started to hump against my younger sister. I only pushed in deep enough to have my knot bump against her outer folds, I had no intention of pushing it inside her this time around...that would happen later when we had reproductive sex together. I kept moving my shaft back and forth through Eva's hot ninetales folds until I couldn't resist the desire to fire my load inside her. I pushed inward as deep as I could without knotting Eva and came, sending hot and thick jets of my semen into her vagina, all of it staying within her canal. The feeling of my cream coating her pussy made Eva murr happily while she cupped her breasts a bit, having a little bit of milk ooze from the nipples in the process. My climax didn't last long, only long enough to give Eva a sample of what she would receive later. Besides, I wanted to save the majority of my current payload for Charlene. After my brief climax ended, I removed my still-erect foxhood from Eva's canal, watching as a fresh creampie bubbled from the space between her legs. It was thick, milky, and loaded with ninetales-grade sperm. A little bit of my creamy filling dribbled onto the ground beneath Eva, leaving a scorch mark in the bare ground from where it came into contact, showing how hot my semen was in this form. With my maleness still hard and throbbing for more, I turned to Charlene and released a puff of smoke from my nose that formed into a heart-shape. "Are you ready for the main event now, Sis?", I asked in a playful manner, showing Charlene that I was more than ready to mount her and continue the 'training'. It didn't take Charlene long to get the point. She promptly got down onto her hands and knees while moving closer to Eva's wide-open legs, watching as a bit more of my cream oozed from Eva's fire vixen hole. "Come on now, Charlene...come get it while it's still hot and fresh", Eva coaxed, referring to my creamy filling inside. She soon placed her tongue against Eva's folds, licking at them slowly to begin with, concentrating on what was coming from her opening. As Charlene was doing this, I noticed that she raised all six of her tails over her back and hoisted her rump slightly in the air, giving me a good look at her vulpix backside. I could feel the body heat emanating from Charlene as her rump faced me, showing that she was indeed horny and in need of my maleness. However, as I stared at Charlene's pussy, I got an idea for a surprise I could give her. I got down onto my hands and knees, then closed my eyes, thinking about transforming from my anthro ninetales form into my non-anthro form. As I did this, my body changed, with my hands becoming paws and my body shrinking down to the size of a typical non-anthro ninetales. The only part of my anatomy that didn't change to adapt the form change was my penis, which remained at 12 inches in length and fully aroused. Once I was done changing forms, I came up behind Charlene and gave her pink vulpix folds a few licks of my tongue, savoring the hot and spicy flavor of the glaze that she produced. It made my nose tingle and my shaft twitch, spraying precum onto the snow beneath me and leaving melted spots in the snowpack. I knew she was ready for me, so I didn't waste any additional time and mounted my sister from behind, latching my front legs around her hips. I covered her as best as I could, resting on top of her sweet-smelling six tails as the tip of my shaft soon met her opening, passing inside a few moments later. As I got comfortable on top of Charlene, I noticed that her tails felt very hot to the touch and would likely burn anyone who wasn't immune to her body heat. "She's really close...I can feel it!", I thought to myself as my front legs clutched her hips and I started to deliver my foxhood to her welcoming vixen hole, humping Charlene at a moderate pace to begin with. Charlene was a bit surprised when she felt me behind her, looking back to see my non-anthro ninetales self humping her as I began to lean into her tails a bit more, savoring the scent and heat she produced. However, she soon placed her hand on the top of my head and stroked it gently. "Seems like someone's eager to get his knot and 'tadpoles' inside me!", Charlene playfully responded while I was being touched, as my front legs kept clinging to her hips firmly and my maleness rubbed against the inside of her hot vulpix folds, spraying precum into her passage. Each time I pushed inward, my knot would kiss against Charlene's outer lips, not enough to cause the bulb to enter her, but enough to let Charlene feel it throb along with the rest of my shaft. I planned on going all the way with her, getting my foxhood as far into Charlene as I could safely reach, delivering a thick payload of cum to her uterus, and turning the tie while doing so. My hope was this would finally be enough to trigger Charlene's transformation. A few moments later, Charlene turned her attention back to Eva, licking at her vaginal folds some more as I could get a view of it from where I was on top of Charlene. Watching as Charlene's tongue slurped against Eva's outer lips helped to fuel my sex drive more as I kept moving back and forth through her canal at an eager pace, beginning to move from side-to-side a bit while doing so. As this happened, the inside of her vagina became hotter to the touch as well as a bit tighter, especially near her opening. Her tails felt as if they were on fire now as I rested on top of them, warming the underside of my body as I began to nuzzle and lick them. "I think this is it", I thought to myself, thinking that all Charlene would need to change into a ninetales was a trigger of some kind, and that trigger would likely be the feeling of my seed rushing into her womb. I wasn't ready to fill her yet, though, I was still getting warmed up inside Charlene, letting my maleness rub vigorously against her wet and warm insides, feeling them contract and expand around it every few moments and letting my bulb kiss against her outer lips repeatedly. Meanwhile, Charlene's nose started to release flame from it while she was 'kissing' Eva's other lips. Of course, in Eva's current form, the flame only helped to tickle our younger sister further as she gasped and her insides spasmed for Charlene. "Ahh...Charlene...you're getting much hotter!", Eva called out, possibly sensing what I already knew from mating with Charlene. Speaking of Charlene, she took Eva's comment as an invitation to go further, actually dipping her tongue into Eva's vixen hole and lapping up the sweetness from within. All the while, Charlene murred happily, enjoying the flavor of Eva's nectar on one end, and my throbbing foxhood on the other end as the tip of it began to lengthen, probing deeper into Charlene while I pushed my bulb against her folds a bit more aggressively. The inside of my testicles churned vigorously, filled with plenty of fresh and eager sperm to be delivered into Charlene once I pushed all the way into her. While I was humping my sister, the tip of my maleness began to lengthen, acting on my desire to inseminate Charlene deeply by using my kitsune powers to deliver my tip to her cervix, and eventually inside her uterus. She felt it push against her cervix and slip through, slowly inching forward as the rest of my foxhood kept rubbing against her vagina. She briefly yipped when I entered her this deeply, but was used to this by now, having taken my long and narrow tip in her womb several times before. I could've made the experience even more exciting for Charlene by allowing my tip to split into two, aiming both of them at her fallopian tubes and letting my semen splatter directly inside them, but I decided against going that far with Charlene, at least not until I was trying to impregnate her. My knot kept bumping against Charlene's outer lips, pushing harder against them as I felt my climax nearing. I knew it wouldn't be too much longer before I had to release my payload and I wanted to make sure that we were completely joined together when that happened. While I was doing this, Charlene kept lapping at the inside of Eva's canal, moving faster as she sensed my knot starting to pass through her outer lips, getting close to entering. Eva's nostrils smoked while she fondled her breasts excitedly, keeping her legs wide open for Charlene. "Yes! Keep going, Charlene! You're making me feel hot and excited down there!", Eva called out gleefully, enjoying the sensation of having her big sister's tongue circling around in her vaginal canal, slurping up gobs of her sweetness. It made Eva quite happy to know that her big sister loved her as much as Charlene did. However, Eva and I were about to show Charlene how much she meant to us. With one more inward thrust, I felt my bulb pass into Charlene's hot and wet vixen hole, becoming engulfed and surrounded by the tightness of her vaginal canal. My knot fed on the heat and wetness of her insides and began growing, all while I tilted my head upward, growled with excitement and shot a powerful flame about 30 feet into the air as my semen started to rush from my balls into my sister's uterus. The instant my cream hit Charlene's insides, I felt a sudden and intense rush of heat along my entire length...a lot like I would experience whenever she ovulated while we had sex, but much more powerful. There was also a bright white light that came from Charlene while I filled her, bright enough to have me turn my head away, even as I was becoming locked inside of her sexually. This was the moment that we all waited for (especially Charlene), she was finally becoming a ninetales. While I was busy filling Charlene's womb, the increase in Charlene's body temperature, combined with the sensation of having Charlene's tongue lashing around inside her vixen hole caused Eva to climax, having an explosive orgasm of her own. Hot and sweet feminine juices ejected from Eva's hole like a volcano spewing hot lava, splattering all over Charlene's face and the ground beneath them. Charlene murred gleefully when Eva climaxed and took in gobs of her nectar while also receiving a healthy filling from my foxhood. I came inside Charlene at full intensity for about a minute before my seed started to come out in short, periodic spurts...acting like it normally would upon knotting. My bulb grew to its full-size, becoming locked tightly inside Charlene while her body hugged and tugged on it, making sure I would stay in her passage until I was finished. Charlene didn't notice that she changed into a ninetales yet, but Eva and I knew, and we intended to let Charlene find out for herself. So, I simply did what I would normally do whenever I was stuck inside a female (or Sapphire), I dismounted Charlene and turned the tie with her, letting nature take its course and enjoying the feeling of her folds tugging against my swollen bulb while I leisurely added more seed to her womb. Once I turned the tie, Charlene turned around to look at how we were joined together, a lot like she usually did at this time. She undoubtedly felt the large pool of my semen in her uterus, slowly growing larger with each successive spurt, all while my length pulsed against her vaginal canal and my knot throbbed as if it had its own heartbeat. In my non-anthro form, my hind legs did not quite reach the ground while I mated with Charlene in her anthro form, they were just a little bit above the ground while my front legs were firmly on the snow-covered ground below. I looked back at my sister while joined to her, wanting to tell her to take a look at what she became, but I couldn't talk in my non-anthro form. Instead, I let a little bit of smoke and flame come out of my mouth, letting it form into heart-shapes for her, all while my seed slowly left my testicles and filled Charlene's womb. For now, there would be no pups growing inside Charlene, but now that she was a ninetales that would be changing as soon as her yiffberries wore off. The tie between Charlene and I lasted about an hour before my testicles were sufficiently drained, being milked quite nicely by the warmer folds of my twin sister. Slowly, my knot began to loosen from her grip, returning to its normal size while she panted from the heat of my cum deep within her reproductive tract. I filled her to the point where she had a small belly bulge down there, one that would remain with her for hours after mating. I worried a little that Eva might get a little jealous about me filling Charlene so much instead of doing it to her. However, Eva would be the first one to get impregnated during our weekend trip, so hopefully that would make up for what I did to Charlene. Speaking of Eva, she got back up onto her feet after climaxing and managed to clean herself in the process, getting her bikini back on. Her sexual appetite (at least for now) had been satisfied enough, but it was certain she would want more attention later...especially from me once her yiffberries wore off. Finally, once my bulb was back to its normal size and my shaft had returned to its normal length and shape, I was able to pull out of Charlene, putting my hind legs on the slushy snowpack. Everything I pumped into Charlene's body remained in her womb as her cervix closed tightly to keep it from escaping while it was still hot and virile. Once I was done mating with Charlene, she stayed on all fours and panted, with all nine of her tails dropping to one side. "Why do I...feel so hot...all over my body?", Charlene asked, sensing the increased body heat from her transformation, still not noticing it yet. While she was asking this question, I changed back into my anthro ninetales form and helped my sister up. I figured it was time she learned the truth. "Charlene, come with me...there's something I think you should see", I mentioned as we walked back towards camp together, with me holding Charlene's hand along the way. I did this both out of my feelings for my twin sister, as well as to help her stay upright. She was still a bit wobbly after what I did to her and it would take a few moments for that sensation to wear off. I brought Charlene over to the truck and told her to take a look in one of the rear-view mirrors on the door. She peeked in along with me and saw that she was now a ninetales...one with the same pink nose Charlene had since she was born. I came over to Charlene's side, nuzzled against her and embraced my twin sister. "Oh my god! It finally happened!", she exclaimed gleefully, nearly jumping for joy over the fact that she finally caught up with me. Once she settled down, I gave Charlene a kiss on the cheek and rubbed the slightly swollen belly she had. At the moment, it was just full of my seed, but in a few weeks there would be some other occupants inside there. "You know what this means, don't you?", I playfully asked Charlene as she immediately murred and nuzzled against me. "It means that you're going to make me a mommy again in a couple days, aren't you?", she responded in a sweet and seductive tone, seeming quite eager to be impregnated from my seed again. "I just hope that our kids are ready for some vulpix siblings", Charlene soon added as I touched my nose to hers and rubbed it gently. "I'm sure it'll be fine, Sis. I think they're ready to have some new brothers and sisters to play with", I mentioned. "Besides, Eddie and Ellie are starting to grow up...it won't be long until they start getting the urge to try what we've been doing for more than 25 years", I added. Charlene and I both knew that Eddie and Ellie displayed the same kind of behavior towards each other as we did back when we were pups. It was only a matter of time before puberty started for both of them. However, unlike what Charlene and I had to go through, Eddie and Ellie would get to do it in an open and caring environment, one where their relationship is fully supported by their parents. Charlene and I then took a few moments to share a deep kiss. It was the first time we did this with both of us in Ninetales form and it felt a lot hotter when I felt Charlene's flame inside my mouth. It made the inside of my throat tingle a bit more and my tails become stiff from all the excitement that she brought to me. After the kiss, Charlene and I decided it was time to get washed up ourselves before making something to eat. To do this, we went over to a nearby stream where Eva melted a hole in the ice to expose the water underneath. We simply blasted the hole with our own flames to open it up wider and heat the water to a comfortable level before getting in. After a few minutes of splashing water over our crotches (and in Charlene's case, her face), we got out of the stream to let it freeze over again, got our clothing on, and turned our attention towards food. To be continued...?