In Heat

by AzureDreamer

Rating: mature
Tags: Porn, Fetish, Gilda, Princess Celestia, Sex, Anthro, Slice of Life, My Little Pony: Friendship is Magic
Length: 7202

celestia arrests gilda with the intention of seducing her

Princess Celestia has a problem.

Her heats come much less often than the average mare's – only once every three hundred years or so. But they make up for that in intensity and in length. For anywhere from several weeks to several months, she is so thoroughly consumed with the need to be bred that she is rendered unable to function. Naturally, the world cannot handle one of the two people in it capable of moving the sun and moon taking a day off, much less a month. The only solution, aside from waiting it out, is to find someone who can fuck her pregnant. And therein lies the problem; most ponies are barely capable of surviving a night with the Princess, much less satisfying her.

But ponies are cross-fertile with a remarkable number of species, some of which are significantly bigger and more durable than others. Princess Celestia has ordered the Royal Guard to track down and capture the first Gryphon they can find to be her mate.

It turns out the first Gryphon they can find is Gilda.

WARNING! CONTAINS ANTHROS, DICK GROWTH, FUTA, HYPER, EXPANSION, GROWTH, MACRO, IMPLIED IMPREGNATION

Cover art by evomanaphy

Commissioned by Theo Winters

Consider donating to my patreon to fund more stories like this!

Published 2018-07-02 22:40:06 UTC
Last updated 2018-07-02 22:40:06 UTC

Breeding

Gilda was no stranger to spending time in a dungeon. If anything, she would almost call herself a fan. If she was in a cell, that meant she didn't have to worry about spending money on food or shelter. Not being allowed to leave was a small price to pay for an otherwise free roof over her head and three also free square meals every day, in her mind. Especially considering that it was an Equestrian dungeon. At the worst of times that meant a frankly unreasonable level of comfort. But this wasn't just any Equestrian dungeon, which segued nicely into why she wasn't nearly as comfortable with being imprisoned in it as she usually was.

This was the Royal Canterlot Dungeons.

The fucking Royal Canterlot Dungeons. Princess fucking Celestia's personal goddamn prison. Normally when Gilda was in a jail cell, it was because she got a bit too loud or a bit too up close and personal with some hapless pony, usually while a bit drunk. But the Royal Canterlot Dungeon was more for people who had committed war crimes or treason or both or worse.

Sure, there was luxury. Even moreso than any other Equestrian prison Gilda had found herself in in the past. It felt less like a prison and more a palace. It had a widescreen TV, a canopy bed, a separate bathroom, a fucking hot tub. And that was just in the rooms she'd explored. There were god knows how many more that she hadn't even been in yet. Were it not for the foot-thick steel door and the complete lack of any windows or sharp objects, she might very well have assumed that it was just another wing of the Royal Palace and not the single most secure prison facility in Equestria, buried several miles beneath the city.

And it had a mint on the pillow.

And everything was huge. That was probably the most unsettling thing about the place. Gilda wasn't used to feeling small, especially not in Equestria. Even by Gryphon standards, Gilda was fairly large for her age. Both her parents had been alphas, both came from a long line of alphas, and Gilda had more than lived up to the trend. She had been fairly large even as a child, but once she hit puberty she sprouted like a weed and hadn't stopped yet. Most gryphons her age barely came to her shoulders, and while there were plenty who outmatched her significantly, those all had significant head starts. Doctors had told her that if she kept up her current rate of growth she might very well surpass 15 feet by the time she hit thirty years old. As it was, ten was still fairly respectable for a gryphon. For a pony, it was practically gigantic. Gilda had never once met a pony who came above her elbow. She loved spending time in Equestria because it made her feel like a giant.

But here, she felt quite the opposite. In fact, the best way she could think to describe it was that she felt the way being around her made exceptionally tall ponies feel. The bed was big enough that four or five of her could climb into it and lay down in a big line, head to foot to head to foot, and there would still be legroom to spare. The TV was almost as big as she was. The doors were twice her height, for fuck's sake. It was like something from a fever dream.

But while the enormous scale of the room was the most unsettling thing about the situation, more concerning was the fact that Gilda wasn't entirely sure what she had done wrong this time. Usually when that was the case she at least had the accompanying blinding headache that indicated a drunken bender was to blame. But she had been entirely, distressingly sober for the entire process of her public arrest and journey down, down, down, into a bright pink cozy little pit beneath Canterlot where she'd promptly be forgotten forever, left to rot in oversized luxury. And for the life of her she had no clue why.

There wasn't really anything that she could do about it, of course, which was why she was more concerned with the scale. There wasn't anything she could do to change things, so she might as well enjoy her time here.

The first thing she did upon reaching that conclusion was to vigorously strip down and head to the hot tub. She'd watched TV and slept in nice beds before, though none of those had been quite so enormous as these were. But this would mark her first chance to use a hot tub period. If there was anything she wanted to make sure she didn't miss out on, it was the thing she hadn't done before. Everything else could wait.

Gilda normally liked to make a show of undressing herself, but normally Gilda had an audience when she undressed herself. She unceremoniously tore off her dirty white t-shirt and slightly undersized jeans, discarding their remains carelessly in a pile in the corner of the room the tub was in. Normally, she would be flexing her arms to show off her considerable muscle definition, hefting one of her head-sized breasts, maybe giving her ample ass a smack. She did none of those things because there wasn't much point, instead opting for a much less dignified scratching of her left buttcheek. Not very sexy, but there wasn't anyone around to see her do it so whatever.

Getting into the tub proved to be a serious challenge. One that Gilda quickly realized was insurmountable. The unfortunate reality was that it, like everything else in the room, had been built with someone much bigger than her in mind. Gilda had heard legends of ancient Primordial Gryphon Kings who lived for hundreds of years and grew to be the size of mountains, and would likely have only felt mildly cramped. To someone of Gilda's much more modest stature, it was like several Equestria Games-standard sized swimming pools put together. She certainly wanted to take it for a spin, but she couldn't. She would drown.

Gilda decided to compromise, sitting on the edge of the tub with her forelegs dangling into the water. It was weirdly relaxing, especially given the situation that Gilda had already broken her resolution not to think about. It wasn't easy to just ignore the fact that she was in Big Girl Prison for real. Not just an overnight stay in the local drunk closet, but an indeterminate sentence in the most maximum of maximum security facilities for a crime she wasn't entirely sure what it was.

“Ugh, this is so laaaaaame.”

“Yes, it's a bit much, isn't it?” Gilda wasn't entirely sure when Princess Celestia had arrived, but given what little she knew about the Equestrian monarch she wasn't particularly surprised. She had a reputation for... eccentricity. Suddenly showing up naked in a prison cell was not particularly out of character for her. “I distinctly remember telling them when it was still under construction that it was frankly unreasonable. You couldn't use this as a swimming pool, much less a hot tub. But no, everyone was dead set on breaking every record, no matter if it made sense to break.” She shrugged her slender shoulders, the motion making her fucking enormous tits jiggle ever so slightly. “Of course, it wouldn't surprise me if at some point tonight we found ourselves wishing this place was a bit bigger.”

“Okay so I have questions.”

“And I have answers!” the Princess replied jovially, leaning over and gently resting her head against Gilda's shoulder. “At least, most likely. I'm not omniscient, but I am likely capable of answering the questions you are likely to ask.”

“Wh-”

“A wonderful starting point. No, you aren't actually in any real trouble. This facility serves, ah, multiple purposes. Sometimes it's used as a prison, but more often it's used as guest accommodations for visiting Gryphon diplomats. Hence the, ah, extravagant size of everything.”

Gilda raised an eyebrow. “I've gotta say, I've met Elder Alphas who would look tiny in here. The weedy little nerds who get stuck on diplomacy duty would probably take a few weeks climbing into the damn bed.”

“Ah, but you must remember that Canterlot is a very old city, and the palace older than that. When this place was freshly built, gryphons and ponies alike tended to be, ah, much larger. And then over the course of subsequent renovations to the palace, newer architects sought to outdo their forefathers and things got a bit out of hoof.”

“Man you talk a lot.”

“I'm told I like the sound of my own voice.”

“Okay then wh-”

“Another excellent question!” Gilda was hardly the most patient person at the best of times, and this was hardly the best of times. Suffice to say, Princess Celestia's repeated interruptions were beginning to grate. She wasn't quite stupid enough to talk back to the ruler of Equestria, of course, but man was it tempting. “As I said, you aren't actually in any legal trouble. The real reason you're here is a bit, ah, personal, and has to do with Alicorn biology. How much do you know about the average pony's estrous cycle?” Not much, but the Princess didn't exactly give her a chance to answer – loved the sound of her own voice indeed.

“Once every month or so, normal mares go into heat, and their body gets quite insistent that they should really be pregnant right about now and if they aren't that they should really be doing something to rectify that. But, as you might guess, normal mares are not typically immortal goddesses of fertility and life. Alicorns such as I go into heat much, much more rarely than normal mares, only about once every three hundred years or so. But in return, where a normal mare's heat lasts a few days, perhaps a week at most, my heats tend to last... well, quite a bit longer.”

“... How much longer are we talking exactly.” There was a sinking feeling dip in the pit of Gilda's stomach. Somehow, she knew that she wasn't going to like the answer, and she certainly didn't like the direction the conversation was going.

“Usually in the ballpark of a month, sometimes less, very rarely more. Once a few thousand years ago I had a heat that lasted for almost a year which was very unpleasant, let me tell you.”

Gilda's jaw dropped. It took her several minutes of awkward silence to regain her composure enough to spit out a “Wh-” which Princess Celestia promptly interrupted with an answer to the question she was going to give.

“Simply put, even with my younger sister back, Equestria can ill afford the mare responsible for controlling the motion of the sun being rendered too mind-numbingly horny to function for a day, much less a month or two. The country can't function without me, so it became a necessity to find a way to cut the heat as short as possible as quickly as possible. And, ah, well, the solution to that is somewhat obvious.” She rubbed her soft, slightly pudgy belly for emphasis. “In the past, it would be quite the ceremony, taking months to find the biggest, manliest, most well endowed stallion in the land. But, well, that was somewhat embarrassing for me and, as I said earlier, in the past ponies tended to be much larger. As it is, I highly doubt there is a pony alive who could lay with me without their spine being thoroughly shattered, let alone satisfy and impregnate me. So I have come to rely on, ah, hardier cross-fertile species. Gryphons are a bit of a personal favourite as they tend to be quite large and to have quite a lot of potential for-”

“Okay hold up, lady,” Gilda interrupted, and Princess Celestia rather surprisingly clammed up, turning to look directly at Gilda for the first time. She had beautiful eyes, Gilda noticed. Deep lavender-purple, shimmering slightly in the atmospheric lighting of the pool room. Gilda awkwardly scooted away, lifting her legs out of the water and turning her body, spreading them wide and giving Princess Celestia a good view of her crotch. “It's gonna be kinda difficult for me to get you pregnant if I don't have a penis.”

“Oh,” Princess Celestia scoffed, waving a dismissive hand. “That's hardly a meaningful barrier.” Gilda raised an eyebrow at that, but before she got a chance to interject Princess Celestia stood up and for the first time Gilda got a feel for just how big she was. Still shorter than Gilda, to be certain, but she was still a good eight feet tall. And while she might not have been taller than Gilda, she was certainly more than her match in numerous other aspects. Her hips were wide, her thighs were thick, and her breasts were fucking massive. Easily a few times the size of her head, and certainly bigger than Gilda's own impressive pair by quite a sizable margin. Gilda didn't get much of a chance to admire them, however, as the Princess placed her foot squarely in the centre of Gilda's chest and quite suddenly the Gryphon found herself lying flat on the floor, her legs still splayed wide.

“Consider it a royal decree,” Celestia growled as her horn was quickly enveloped in an aura of golden light. “I'd say five feet's a good starting point. We can always go bigger, after all.”

Gilda wasn't entirely unused to pony magic. She was intimately familiar with pegasus magic – it was ultimately the same stuff that gryphons used, and she had been around pegasi her entire life. Earth pony magic was a bit more alien to her, but it was hard to interact with pony society at large without encountering a shitton of earth ponies. Beyond that, their brand of magic wasn't exactly rocket science. Even someone with Gilda's admittedly limited level of book smarts could wrap her head around the basic concepts, and there wasn't much more to earth pony magic than the basic concepts. Simple and broad, almost to the point of complete abstraction. Earth Ponies were just Earth Ponies.

Unicorn magic was another story entirely. Almost the exact opposite, in many ways. For starters, unicorns were significantly rarer than the other two breeds combined – Gilda had only really ever interacted with that one friend of Dash's. For another, unicorn magic was much more varied and much more direct than earth pony or pegasus magic. If Gilda had rarely encountered unicorns, she couldn't recall ever having unicorn magic used on her directly until now.

It felt weird. That was the only word that came immediately to mind. Gilda had never been good at metaphorical language, so the only way she could really describe it was bluntly, for what it was. A heat, a tingling, a pressure just above her crotch, and then the very pleasant sensation of flesh erupting into being. Thick, angry red flesh, glistening with musky sweat. An enormous knot bulged just above the base, another smaller one just above that, before tapering to a dangerously pointed head. And oh, it was big. There were adult ponies who were smaller than Gilda's new cock. There had been a time not too long ago where Gilda had been smaller than her new cock. Five solid feet of fuckstick, half as long as she was tall, with girth to match and a set of fat, fertile balls the size of her head to provide the ample supply of hot seed that erupted forth in violent orgasm as it came into existence where once there had been nothing. Arcs of potent gryphon seed painted the floor and her companion in thick streaks of off-white. Gallons of the fuckin' stuff.

“Well, we're going to have to work on your volume, but the size is good. Definitely off to a promising start! Now, I believe you were going to breed me?”

Gilda needed a moment to process this turn of events. A moment which the Princess was clearly not going to give her. She strode forward, dropping to her knees and shoving her fat tits around Gilda's shaft. “Let's start with some foreplay, shall we? There's nothing that breaks the ice quite so well as a nice titfuck.”

Gilda had never had a titfuck before in her life, for obvious reasons. She had also never given one – her interactions with penises in general were severely limited. Just having a cock was a profoundly bizarre sensation, vaguely uncomfortable but not in a bad way. Adding the warmth of Celestia's body heat, the friction of alabaster fur rubbing against sensitive flesh, the all-encompassing softness, the fucking tightness. Celestia pushed herself up and down Gilda's shaft, using her entire body to tease the five-foot fuckstick. Her legs wrapped their way around the shaft, her wet cunt grinding needily against it. God, it was hot. Almost enough that it hurt, but not quite to that point. The heat quickly spread throughout the rest of Celestia's body, especially her tits. Like her cock was being enveloped by twin suns.

Running on raw animal instinct, Gilda reached up and grabbed Celestia's milksacks. It wasn't just her cockflesh being unusually sensitive – her hands darted away immediately on making contact from the sheer heat of Princess Celestia's flesh. “Oh, yes, my apologies. As a sun goddess I sometimes find myself, ah, getting a bit too hot to handle? Here, I'll cast a temperature dampening spell on you, that should help.”

There was another sharp spark of electricity that jolted down Gilda's spine, and Celestia's body temperature seemed to take a sudden nosedive. She still felt hot, but more reasonably hot for someone in the middle of a particularly bad heat. Still, the difference was jarring and disorientating – it took a few moments for Gilda to recover enough to resume her participation in the fun. Moments that Celestia didn't need. After casting the spell, she immediately resumed grinding against Gilda's cock, squeezing and writhing and licking. The constant, unrelenting attention was almost too much for Gilda to bear, and already her cock had begun leaking a steady stream of precum.

“Oh, ready for more so soon after your last climax? Impressive! You must have a bit of alpha in your blood, then. Mother or father?”

“Mnn, both,” Gilda managed to reply, forcing the fog of arousal aside through sheer force of will. “Most 'a my family were alphas, going back generations.” It was something of a point of pride for Gilda. The blood of alphas ran through her veins, going back more than a thousand years.

“Oh, really?” Celestia grinned eagerly on hearing that. “A purebred Gryphon Alpha going back generations, you say? Oh, yes, I think the guards made an excellent decision, choosing you.”

“Huh?” In a strange twist of events, though Gilda had been able to focus through Celestia's ministrations, the Princess grinding to a halt was enough to throw her for a loop.

“You see, there are certain... quirks of Gryphon anatomy that only really express themselves in purebred hermaphrodite Alphas. They aren't common knowledge now, even among gryphons, because hermaphrodite alphas are so rare in modern times. I don't believe one has existed in more than five hundred years for, ah, reasons that should become obvious. Or at least not until now.” Celestia slowly extricated herself from Gilda's cock. She took a few steps back, elegantly rotating around to face away from Gilda. “Allow me to demonstrate.” In one quick, smooth motion, she bowed down onto her knees, fat tits pressed onto the ground and ass waving enticingly in the air. “Enough foreplay. It's time for you to fuck me.”

Gilda did not need to be told twice. Or at all, really – even as Celestia gave the order her body was getting up of its own accord. She strode forward as confidently as was physically possible with a cock half as long as she was tall. Which, shockingly, wasn't very. The rock-hard five foot length threw off her balance quite badly, and the fat, full balls were, it turned out, a bit too fat and full for her to be capable of walking like a normal person. She waddled awkwardly, but it was the most confident and dominant waddle she could manage, only to run into another issue. Her cock was so big that her hands couldn't actually reach Celestia in order to steady herself and put the damn thing in.

“Here, let me help speed things up a bit,” Celestia said softly, and Gilda found her hips and cock enveloped in a warm golden light which gently guided her the rest of the way to her goal.

“I coulda handled it,” she muttered sullenly as the pointed head of her cock pressed against Celestia's soaking wet pussy. Its tapered shape was, it turned out, a solid advantage in this situation. In spite of the absurdly excessive size of it, it slid into the tight hole with ease, like they had been made for each other. Celestia continued to use her magic to slowly (more slowly than Gilda would really have preferred) guide the fat Gryphon cock into its destination for two and a half feet, at which point Gilda could actually fucking reach her partner's expansive ass. “Ha! Now it's time for me to take the lead.”

“If you must, I suppose I won't stop you.”

Gilda grunted in annoyance, and grabbed Celestia roughly by the hips. “Here, lemme show you what a real fucking's like.”

Having an actual real part-of-her-body cock was new to Gilda, but she wasn't a stranger to being the boy during sex. She had fairly extensive experience with strap-ons, and she put that experience to good use by squeezing Celestia's hips and plunging the remaining two and a half feet of cock in with one fell thrust. The alicorn princess let out a strangled, gurgling gasp as the cock, three feet shorter than she was, stretched and deformed her body in a way that should really have probably been more grotesque than it was. It helped that Celestia was clearly enjoying it, an unsteady and mindless grin of pleasure spread across her face and her tongue lolling out like something out of a bad neighponese porno comic. And oh man did it feel fuckin' good. Gilda had exactly zero context for what it felt like to give vaginal sex in normal situations, but there was absolutely no fuckin' way in Tartarus that it was normally this tight. And it was moving, pulsing and undulating around her shaft like countless hands wrapped around its length giving it a good milking.

“You okay?” she managed to force out through the overwhelming sensation of pleasure.

“Don't worry about me. I'm a goddess, I'm not made of glass. Now stop wasting time talking and breed me.”

“Of course, your Majesty,” Gilda replied with about as much snark as she was capable of mustering given the situation, before steadying herself against Celestia's body and pulling out as far as physically possible and then plunging her full length back in to the hilt. There was a series of wet popping sounds as her knots exited Celestia and then another as they entered, fading into the background amongst the wet thwaps of her thrusting, in and out and in and out like fucking construction equipment. Her body was practically moving on its own volition while her mind concentrated more on her mounting second orgasm. There was an unfamiliar pressure building in her abdomen, and a mounting sensation of fullness spreading out from the pit of her stomach to the rest of her body. A burning sensation, like fire was flowing through her veins instead of blood. A tightness approaching the point of pain in her muscles. Even her bones felt weird – Gilda was unaware it was even possible to feel your bones at all. That was probably the first real red flag that no, this wasn't what orgasms were supposed to feel like. “Gnnnggg what the fuck's happeningggggggggg.”

“That,” Celestia said, her tone of voice almost indistinguishable from how it had been before a tree trunk of a cock had been roughly shoved into her. “Would be the quirks of gryphon anatomy I mentioned.”

Gilda let out a low, rumbling groan as she tumbled headfirst over the edge of orgasm. Her cock bulged at the base, even more obscenely than it already was as a truly massive volume of cum made its way up through five feet of shaft and erupted into Celestia with a wet splort and a rubbery stretching sound. That tightness vanished, replaced with a warm, tingling sensation of her body becoming bigger.

“Cumming makes you grow~”

“I'm sorry, cumming makes me fucking what?!” Gilda snapped even as she felt Celestia get tighter around her swelling shaft. She lurched bigger in large, uneven spurts of size, several inches at a time. She found herself collapsing forward onto her hands and knees, her body dwarfing the Princess beneath her. It felt like each blast of semen her body unleashed was bigger than the last. More and more, bigger and bigger. She could feel herself growing to the point where Celestia was lifted off the ground, and she quickly rolled herself over onto her back. She managed a few more good spurts of cum before slowing down and stopping at approximately fifteen feet tall, going by the relative change in the size difference between herself and the princess.

And speaking of the change in size difference, Princess Celestia had previously had taken the whole damn five foot length of Gilda's cock, Gilda's cock was decidedly more than five feet now. In combination with the sheer amount of cum that had been pumped into her, Celestia contained just about half of the length – it had to be almost as big as she was, so even that much was impressive. Her belly was so filled with cum that it outsized both of her tits combined. Almost bigger than the entire rest of her – Gilda doubted she'd be capable of moving under her own power.

“That's a good start, I would say. A bit of cooldown time then on to round two?”

Gilda's eyes widened in quiet horror. “Round two? Lady, if I cum again I won't fit in you!”

“Oh, please, do you really think something like your cock outgrowing me would slow me down? I am in heat and we are not done here until I am well and truly pregnant.” Celestia slowly rotated herself until she was facing Gilda, still impaled on her cock. “That was quite the impressive load for your first time, but I believe I have already mentioned being a goddess of life and fertility. This isn't nearly enough to satisfy me. Now, we are going to keep going until I am satisfied or until you are incapable of contributing any further, whichever comes first.”

“Okay, that's all well and good, ma'am, but if one orgasm is enough to leave my cock as big as you are, how do you expect to fit after the next one?”

“My dear,” Celestia replied, a smug smirk on her face. “You seem to be under the misapprehension that fifteen feet is particularly big. I believe I told you that this palace was built in a time when ponies and Gryphons alike were much bigger than they are today? I am from that time. Fifteen feet is impressive for a Gryphon as young as you are today, but to me it's nothing.”

“Okay.” Gilda felt taken aback. Almost intimidated by the pony, in spite of being just a bit less than twice her size. Somehow, she knew that the Princess wasn't just blowing hot air. There was a certain weight behind her words. Still, that was just a gut feeling. If her gut was right but she made the decision to end things here, she would miss out on some sex. But if her gut was wrong and she trusted it anyway, that would probably count as treason. “Okay, look, I can't exactly go anywhere, but I don't wanna end up in here for real.”

Celestia laughed at this. “I'm thousands of years old, Gilda. If anyone here is in danger of being fucked to death it's you. Besides, what kind of sun goddess worth her salt is only eight feet tall?”

“Wait hold on, what?”

Celestia did not respond to Gilda's question. “After all, ponies in the past were much bigger than you are right now, and what kind of monarch is smaller than her subjects? I'm thinking thirty feet is a good starting point, but we'll see how well you keep up.” Gilda opened her mouth to interject a question, but found herself abruptly cut off as Celestia grabbed her beak, holding it shut. The Princess was surprisingly strong. “That's enough talk for now, I think,” she said calmly as the golden glow of her magic enveloped her and she began to grow.

Where Gilda's growth spurt had been wild and erratic and violent, Celestia's flowed smoothly from one inch into the next. Like a river flowing gently down a mountainside, making its way slowly but inexorably to the ocean. A bit of a corny metaphor, but Gilda wasn't exactly good at metaphors. The point was that, over the course of a few seconds, eight feet transitioned smoothly into nine. Nine feet transitioned smoothly into ten. Ten to eleven, eleven to twelve, and so on and so forth with no signs of slowing down. If anything, her growth seemed to be picking up the pace as it went on. She slid her way down Gilda's seven foot shaft, and her overstuffed womb slowly began to shrink down in relation to the rest of her.

“I seem to have caught up with you. Best pick up the pace or you're going to be in an unpleasant position.”

It was easy for her to say, but cumming on command wasn't something Gilda was capable of doing. She could only watch helplessly as Celestia passed sixteen, seventeen, eighteen feet. “Mmmm, come on, thrust or somethin',” Celestia muttered, for the first time really dropping the regal tone. “I'm not a big fan of fucking people smaller than me, short stuff.”

That hit a nerve. If there was one thing in the world Gilda took pride in, it was being big. Not necessarily the biggest, but big. Bigger than most people she was likely to ever interact with on a regular basis. She hadn't been called short very often in her lifetime, for obvious reasons, but it never failed to piss her off. With a roar nestled somewhere between rage and need, Gilda grabbed Celestia by her legs and hefted, shifting the balance and knocking the still growing goddess flat onto her back. She held Celestia's legs over her head and thrust wildly into her greedy cunt. “How's this for short stuff, bitch.”

“Oh fuck yeah, this is more like it! More! Harder!” Normally, Gilda would have been upset that Celestia was enjoying it. But, well, she wasn't calling her short anymore. For that reason alone, she was more than happy to comply with her highness's commands. In addition to being big, she was also very strong. She rarely got the chance to utilize her full strength in Equestria – she had to use a feather-light touch even when just walking around Ponyville for fear of causing irreparable damage to the architecture. Princess Celestia, though, was clearly significantly more durable than the average Equestrian doorknob. Gilda didn't bother holding back, fucking like a goddamn jackhammer and then more.

And yet it still wasn't enough. Her head went from just below eye level to just barely reaching Celestia's chin, to being buried in expansive titflesh. Titflesh which was, she noted with mild annoyance, growing slightly faster than the rest of Celestia. And, more pointedly, she found her cock being hugged more and more loosely by the expanding deity. Seven and a half feet of penis had become almost normal in proportion to the growing giantess. Which was disappointing in many ways, but the most important was that it just didn't feel as good. She could feel her orgasm building, a tightness in her gut and an audible rumbling from her fat, full balls even as they smacked against Celestia's thighs with a repeated rhythmic plap. But she remained just barely on the edge, climax dangling just out of reach.

“You're doing well, don't worry,” Celestia said, her voice warm and motherly. “Just keep it up and if you haven't finished by the time I'm done growing I'll give things a little extra push to the finish line.”

“I don't need your help,” Gilda muttered to herself even as she felt Celestia get bigger and bigger beneath her. She attempted to pick up the pace, but she was already fucking as fast as she could fuck and it wasn't really working.

“Don't think of it as help, dear,” Celestia replied patiently. “Think of it as removing an unfair advantage.” The princess reached down and gently embraced Gilda from behind, pressing her head deep into alabaster cleavage. They had been absolutely massive before, several times the size of Celestia's head, but now there were almost certainly full grown ponies who could get completely lost in the vast canyon. If anything, Gilda felt like they were growing disproportionately fast compared to the rest of her, though admittedly she didn't exactly have the best view of the big picture. Given her position it would be unsurprising if their size felt exaggerated, but whatever. The point was that they felt comforting. She felt safe. Warm. Loved. Which was odd, given she'd known the Princess for all of ten minutes. Possibly more, though her sense of time was almost as skewed as her sense of scale.

It took her a moment to realize that sensation of comfort wasn't entirely natural. Her mounting climax, which had begun to wane, suddenly returned, bouncing back to its previous intensity and then more. Pressure mounted, blood burned, muscles tightened, bones tingled, and then everything exploded outwards like a fucking bomb went off in her loins. “Cuumingggggg~” she cried as her third climax of the evening struck her and once again she began to grow.

“Yesssssss,” Celestia practically hissed in joy as, once again, her gut surged outwards from the sheer volume of Gilda's output. Even with the gryphon being at most half her height, her output was obscene. A torrent of hot, fertile seed flooded her womb like a dam that had been built to keep back an ocean had just broken unexpectedly and the entire river valley was just absolutely royally fucked. And speaking of fucked, boy howdy was Celestia getting just that. With every voluminous burst of baby batter unleashed, Gilda got several feet bigger, and every foot of height Gilda put on gave her more strength, more leverage, more cock with which to breed the goddess beneath her. “Fuck me!” she cried, voice tinged with a desperate need as, for the second time, that graceful facade shattered to reveal the cum-hungry slut her heat had transformed her into. “Fuck me! Breed me! Fuck me pregnant and then fuck me more! Fill me with so many babies that the world could end out there and in eleven months there'd be overpopulation concerns! And then fuck me some more! More! More!”

Gilda didn't need to be told twice, though Celestia seemed intent on telling her significantly more than twice. Not that she minded – watching Princess motherfucking Celestia completely and utterly lose her shit beneath her was a huge fucking turn-on. Also a turn on, it turned out, was growing. She didn't even need the stimulation of thrusting in order to keep up the level of arousal necessary to keep cumming and cumming, which was good because her knots had gotten big enough that thrusting had become problematic. Just the sensation of getting bigger was enough for her to keep going and going and going with no end in sight. Fuck, if anything her output was increasing. Maybe getting huge really did feel that good, maybe she'd hit some kind of threshold where her balls were producing more cum than her cock was putting out, or maybe Celestia was giving her some magical assistance. She didn't give a fuck. She just kept right on going and going and going.

And, while she was on the subject of turnons, Celestia had definitely been growing her tits faster than the rest of her. They had definitely gained two or three extra head sizes since Gilda had last got a good look at them. They dominated her torso, hanging heavy and firm and big. And, she noted vaguely through the haze of orgasm, leaky. It wasn't really surprising, but given that she was having a very difficult time thinking straight through the still ongoing climax – which she was pretty sure should have ended by now and going this long was probably unhealthy – she couldn't quite grasp exactly what was happening. Things seemed to be moving in slow motion, hazy and vague, like a dream sequence in an old soap opera. Like there was a sort of big, fluffy blanket in between her mind and her body, preventing her from properly processing what was going on. Likely as some sort of coping mechanism to deal with the fact that she had been cumming for several minutes now and was showing no signs of stopping.

Idly, almost subconsciously, she reached down and grabbed Celestia's tits, giving them a good squeeze. They fit oddly well in her hands given how enormous they were – a testament to how big she'd gotten, though Celestia herself had started to speed up her own growth in an effort to even things out. Whatever, Gilda didn't care. She'd rather their sizes remain relatively even so they could keep up meaningful interaction. Especially if it meant that she could more realistically fondle them as they grew, swelling bigger in her grasp. She grinned sloppily, like she was drunk on anything other than the rush of growth and overwhelming pleasure. She squeezed, delighting in the sensation of flowing milk against her talons. The only thing about Celestia that came close to matching her glorious titties in terms of raw size was her big fat cum-filled belly. Celestia's own growth was just barely enough to keep up with Gilda's output, and then only barely. Like her tits, Gilda could feel her womb fill with gallons upon gallons upon gallons of baby batter. Fuck, given that she was in heat, there was no fucking way that it hadn't taken by this point.

But there was, she supposed, no harm in keeping it up just a little longer.

Rainbow Dash was in a foul mood. Normally she was one of the most laid back ponies in all of Equestria – it took something special to get her riled up quite like this. Things like having to do extra work because someone screwed up, or Rarity brainwashing one of her friends into a mindless sex slave again. That kind of thing. But all of that felt like minor annoyances compared to what had gotten her worked up today.

“Outta my way,” she snapped, roughly shoving a Royal Guard aside. The guard, for his part, seemed thoroughly willing to take the abuse, which was nice of him. She needed that little bit of catharsis, and she got the impression the guards knew that she needed it. After all, one of her oldest friends had been fucking arrested for no goddamn reason. Of course she was pissed off about that. Who wouldn't be?

It wasn't like Gilda didn't have a history of trouble with the law. She was more than happy to let Gilda do her time when she'd actually done things, but as far as she could gather Gilda had just been plucked off the street and dumped into a prison otherwise reserved for people who killed and ate babies. That wasn't something Dash was willing to just stand idly by and ignore. So she stormed her way down, down, down into the dark, forgotten depths of Canterlot.

The doorway to the dungeons proper was intimidatingly large, almost enough to make Gilda seem small. Which was saying a lot, given how enormous Gilda was. The royal guard posted at the entrance nodded to her. “Heard you were comin',” he said, tersely. “Sorry about this, apparently it was some kinda clerical error?”

“Ugh,” Dash grunted sullenly. “Well at least you're fixing it as soon as possible.”

“Yeah, we'd have dealt with this sooner but we haven't been able to contact Princess Celestia in like a week. Here, I'll just let you in.” There was a loud buzzing noise, the enormous doorway slowly creaked its way open and Dash made her way inside.

The first thing she noticed was the smell. The place absolutely reeked of sex. Like in the two days in between Gilda's arrest and Dash arriving to set the record straight, Gilda had done nothing but get constantly gangbanged by the entire royal guard. The air was hot and moist and thick, and Dash found herself gagging violently. The whole place was completely trashed. Not one single piece of furniture was intact, and most of the walls and ceilings appeared to have been knocked over. The culprit being directly in front of her – a vast wall of brown furred flesh, and above it an equally vast wall of white furred flesh interspersed with a distressingly familiar cutie mark.

“Oh god,” she muttered to herself. “Not this shit again.”

“Ah, Rainbow Dash! Good to see you again!”

“Hey, Dash. 'sup?”

Dash just stared in quiet exasperation, lamenting the choices she made that led her to this point. “Hey Gilda,” she replied wearily to the gigantic gryphon. It was difficult to get a good look at either Gilda or the Princess, given how phenomenally vast the two had become. The vast majority of the space in the room was taken up by either the gryphon or the goddess. Dash cringed slightly, silently thanking Luna that she'd arrived before they outgrew Canterlot Mountain (again). “You're allowed to leave.”

“Yeah, gimme a minute, we're really starting to get into the swing of things.”

“Oh my god,” Dash muttered, just quietly enough that it was hopefully not audible to either of the giants. Her mind raced, desperately trying to come up with some clever way to avert the inevitable disaster and coming up with nothing.

“Actually, I'm sure neither of us would object if you felt like joining in. It would take a little bit of growth magic, but that's not particularly difficult.”

“You heard the lady, Dash. Wanna make this a threesome?”

Dash paused for a moment, then let out a deep, deep, deep sigh. “You know what? No. I think I'm good.”