The Experiments

by Trixie by Night

First published

Twilight Sparkle transformed her friends into monsters 'for the greater good' (mix of sex and horror)

It's been a thousand years of Twilight's reign. Equestria is the safest and most plentiful land across the world. All thanks to Princess Twilight Sparkle, and the sacrifice her friends made.

At least that's what the propaganda says. In reality, Twilight was just afraid of loosing her friend to time. She did everything to ensue they would always be there for her. For decades, she investigated, experimented and finally transformed her friends' bodies and minds to withstand eternity by her side.

Nothing was forbidden. Nothing was 'too far'.


Plotless fetish diatribe with dark themes. Inspired in the early grimdark fics like Pages of Harmony and Lil Miss Rarity. Ponies are anthropomorphic (mostly).
Contains themes of gender identity and expression. Transphobe go away.
Fetishes include, but not limited to: body modifications, mind altering (consented), corruption (consented), gender fluidity (futanari), growth, inflation, hyper sizes, bondage, breeding, lactation, endless fluids, over stimulation, body horror, regular horror.
All acts are consented and between adults.

Prologue: The Entrance

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Princes Twilight Sparkle walked down the hallways of Royal Palace of Neo Canterlot, from her throne room to the Forbidden Chambers. Although it's been a thousand years already since the day of her coronation as Princess of Equestria, that milestone was almost a decade behind her. This week thought, would be the real millennium since she became who she is as a rule.

Since she became what she is now.

The legion of guards and servants around her stood at attention or bowed as she passed them. Every century since she took notice of a cult forming around her, she tried to dissuade her ponies from worshipping her. She was their servant, not the other way around. But after nine attempts, she gave up. Maybe it was in their nature to recognize some hierarchy in her. Some sort of religious maternal figure.

She snickered to herself thinking about the cruel, twisted irony of that.

After traversing most of her castle, she began her descent down the final set of stairs. She went alone, as no pony dared to ever go down them. Neither was any creature allowed even to the entrance of the chambers. Only Princess Twilight herself could witness their blasphemous contents, as per her own instructions.

There were hidden in the depths of the Royal Palace. Lower than the dungeons, and the catacombs, the Forbidden Chambers were built around and from the buried remains of what used to be Ponyville. Twilight finally reached the entrance to them, flaring up her horn to open it. The stone door became illuminated by the dark pink glow of her magic, revealing a pattern or runes, arranged in a circuit of Twilight's own design. The spell wasn't too complex, but it required two components; the raw magical energy of the last remaining alicorn, and showing no shame.

As she poured her power, she bit her lip. She unstrapped her dress, letting it dissolve from her own irradiating magic. It was the only covering she wore in the trajectory. Being almost naked in front of all her subjects helped her prepare. Despite the centuries of age, her body didn't look a day older than her early thirties. Her breast were modestly sized, but stood firm as she began to cup herself, making her nipples erect as she gently brushed her fingers over them, one by one.

Twilight moaned openly, sliding down her own hands down her sides. She opened her mouth, releasing an ample amount of saliva as her tongue hung twice longer than any normal mare. She bowed her head, lifting her breast just a bit in order to reach her own nipples, licking each one at a time. Small drops of milk came out, which she scooped with the tip of her tongue and suckled into her mouth. Tasting herself, she sat down on the floor in front of the door, opening her legs.

She looked down at her penis, constrained by a small cage welded shut. She put it on about a decade ago. With one of her hands, Twilight started caressing her groin around her trapped genitalia. It wasn't as good as stroking herself, but it wouldn't last. The steel cage began to crack by the strength of her arousal. Twilight lifted one of her breasts with her other hand, suckling the areola with her lips directly this time as she kept caressing around the cage, getting more vigorous by the second.

Finally, the cage snapped, falling off her growing penis as the sound inside her urethra slid up. She let her breast go, holding her other hand still on her shaft as she contemplated the metallic rod finally exiting her penis, followed by so much precum, it made a puddle between her open legs. Twilight's penis was enormous, more than any other of her ponies. She lied down on her back this time, letting her penis rest across her abdomen, reaching just a bit under her breasts, before she started to stroke herself.

Twilight's wings flapped against the floor as she kept moving her hands up and down her large penis. In that position, she also pushed her breasts together with her upper arms, slightly squeezing them and making more drops of milk to come out. Same from her tip, pouring a nearly constant stream of precum over herself. Twilight lifter and bent her legs, curling up as she alternated her hands from her penis to her breasts, using her long tongue to lick both nipples and her tip, greedily drinking either fluid.

It didn't take long for her body to get soaked in her endless fluids.

She kept pushing her hips against herself, as her tip finally reached for her waiting lips. She Twilight let go of her breasts and shaft so she could put her palms on her butt, caressing her own cheeks for a moment, before she could push herself some more. She licked, kissed and then started to suckle herself, holding her hands firmly, only moving them in very small circles.

With her legs in the air, bent from pleasure, from her anus started to emerge the final piece. A ver large dildo slid up from her raised butt, pushed out after being inside her since at least two decades. The giant metallic phallus almost fell off her, if not for her putting her middle finger on the center of its based and started to push. Then letting it slide off again, then pushing. Her wings stopped flapping and instead began to close on her curled up body, rubbing her own feathers over her soaked skin, as she pleasured herself in a ball of lust.

Her entire body tensed up, then she unfolded, releasing one ample load of semen in the air after another. The metallic dildo was pushed out, leaving her anus gaping. She was panting on the floor over her back, making her breast rise up and down. Her wings, legs and arms were all spread open, as she slowly came back from the small death of the orgasm.

Twilight was smiling widely without even a sign of having shame. After all was said and done, that was who she had become, who she was. What she was; lust and shamelessness.

Her smile didn't die down as she stood up in front of the door, crossing her arms under her breasts as the door's inner mechanism made it over back from the stone wall, and then to a side to let the way open. With her magic returned from the door, Twilight quickly evaporated any fluids still on her body, as well as replenishing herself for what she was about to do. She needed to be in her best shape for what came next.

Twilight was now ready to visit her friends.

She walked into the Forbidden Chambers, being devoured by the darkness as the door closed behind her.

01. Applejack

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Twilight stood in the middle of the Forbidden Chambers.

She looked around the circular room. Not counting the entrance blended into the wall so smoothly it basically disappeared, there were six other doors arranged symmetrically and drawing a six pointed star on the floor, just like their cutie mark. Each on of the doors had engraved one of her friends' cutie mark, plus one with Twilight's, all made of the same stone as the walls. A soft dark marble that caressed the skin of her naked feet. Enchanted to remain warm and softened if needed, as well as vanishing any dust or dirt that may make its way down there. Not that anything could

The chamber was nigh indestructible and impenetrable for anything less powerful than herself. And over a millennia, there was no creature left who had even a fraction of the power Twilight possessed. She licked her lips at the thought. The only thing really restraining her was her own conscience.

But at any moment, she could just burst out of the chambers up to Neo Canterlot and turn the country, even the world in her plaything. Every living creature an extension of her will, every body available dedicated to her pleasure. And why not? She sacrificed so much to be powerful enough for them. Every pony born in the last millennium owed their existence to her. In return, she didn't owe them anything.

Twilight snapped out of her power fantasy. She didn't realize when she hung her tongue or began stroking herself. She giggled, amused by the thought of anyone outside ever discovering the truth. As the Princess of Equestria, she was so calm, collected and caressing, every pony looked up at her as a leader and a role model. She was their guardian goddess. But down there, in her marble chamber, Twilight Sparkle could be as depraved as a demon. She kept smiling, still caressing her body over with her hands and wings, as her tongue hung down to her neckline, marinating herself in her own lust.

That was her more honest face. That's why she always smiled when indulging herself down at the chambers.

That little daydream actually gave her inspiration for her first visit of the week. Applejack's chamber was made specifically to contain power. It wouldn't matter how much power either of them released inside of it, the room would compensate for that. And Twilight felt a need to play with power. Even if she had become power itself, she wasn't the only powerful creature around. She made sure her friends all could match her, each in a different individual way. Maybe even top her if they worked together.

Or if Twilight willing let them take her. She couldn't stop herself recalling the times she let any of them do as they wished with her body. If she was lust, then she was also her friends' lust. They all had such wonderful desires that made her droll, and harden, and sweat, and crave, and need. Steadying herself out her fantasizing and self pleasure, she walked over to the first door with three apples engraved over it.

It had the same lock enchantments from the entrance. But inside the chambers, Twilight had no inhibitions, so her presence alone was enough to trigger the power and lust spells with just a touch of her fingertip over the door. It slid out of its frame and to a side, leaving the way open for her to cross.

Inside the chamber, it looked like an open field. Twilight looked up as the door behind her vanished, having to put a hand over her eyes to cover them from the shinning of the sun. The sky looked so big and endless, as the green around her extended beyond her sight. It was like back at Sweet Apple Acres, which invaded Twilight with nostalgia for those simpler days. She kneeled down to feel the caressing of the grass on her palms. Some of it was tall enough to tickle her ass and penis as she lowered her hips.

Twilight began to walk, slowly calming down from her pleasure haze, allowing one of the main spells in the chamber to act on her body. It brought down the more complex thoughts and emotions for anyone inside it, bringing them down to a primal state of calm. As such, her steps became slower, letting herself enjoy the mix of warm sunlight and fresh breeze over her naked body, permeating her fur and feeling it on her skin. The sounds around her of threes moved by the wind, rustling leaves and carrying the vegetation's aromas for her to smell, as the grass beneath her feet caressed her with every step.

On her way, she found a three with fresh apples. She took one, smelling it carefully before taking her first bite. The sugary juices and the firm texture of the fruit filled her mouth. She chewed it very slowly before swallowing, taking in every sensation before going for a second bite as she kept walking. Here eyes half closed as every sense on her body was stimulated one way or another. The lust came back, but different. Twilight didn't crave excess anymore. She just wanted to feel pleasure.

After she lost track of time walking, the softness was finally interrupted by a rumbling. Twilight finished her apple and stood at the edge of the grass, where the working fields started. There, working the endless land by themself, was her first success on display. Twilight sat down on the grass to appreciate the body she created for her friend.

Applejack body was changed in order to resist anything time could throw at them, which made them outright invulnerable. They stopped wearing any clothes by the first decade of the change, not really needing any of its protection, and slowly forgetting about their modesty as an effect of shedding their mortality. Though, Twilight didn't stop at just making them invulnerable. Instead, she also made Applejack's body to be able to nourish itself from any nutrient and energy it could catch. Be it the simplest of meals, or even the light of the sun. Through the last millennium, they had grown strong without limits.

The sounds alone they made were huge. Breathing from Applejack was outright seismic. A sigh for them could as well be a hurricane. Their heartbeat could be heard by the naked ear. It was deafening for mortal ponies. Not to talk about their body overall. Their muscles rubbed as they moved, making a stretching noise just from opening and closing their powerful hand. Just stepping on too hard could trigger earthquakes or worse. Outside of their chamber, Applejack would be a natural disaster unleashed.

It changed their body's shape too. they had so much raw energy inside them, that their mental self image reflected on their body. In order to accommodate themself, as well as their own desires, Applejack also developed other features that showed of the power they now wielded. The first apparent change were the two bovine horns adorning their head. At first they insisted they gave a practical use of the strength of their head and neck. They said the same about their feet becoming hooves, and their tail became thicker and less equine. But as the changes went on and their body resembled more a minotaur and more androgynous, it became apparent they were embracing a new identity too.

Their fur also became shorter and thinner, leaving their impenetrable skin open to the elements, and a perfect view of their muscles in motion as they pushed the gigantic plow through the field. By the strength they displayed so casually, those muscles should be overdeveloped and take over their body. Instead, they all grew in harmony with the rest of their body. It didn't keep its feminine outline, becoming androgynous the more they grew. Instead of a thin waist, they showed off a set of abdominal muscles that could crush the hardest stones, giving their torso the appearance of a brick wall. In comparison, their ass and breasts didn't grow too much, but were kept large and firm by the titanic pectorals and gluteus muscles underneath them. Size that extended across their arms and legs, which they kept flexing and pushing to work on

Applejack needed to be constantly working, spending the energy. Otherwise, their already limitless strength would burst out in more destructive ways. And despite how much they changed physically and mentally, they were still fundamentally Applejack. So they gladly took over an eternal workload that would provide a useful outlet to their ever-growing power. It was even their suggestion to start with a barren wasteland when Twilight made their chamber. Since their own earth pony magic would provide with sustenance for the land, and they needed any extra work anyways, Twilight only create a flat landscape of nothing but earth and a solar cycle.

In just a few decades, they worked the empty space into a fertile and varied land, shaped as a perfect recreation of their old home, always expanding along their strength. They cultivated literally every plant species in existence, sending the products to the outside through Twilight's magic. By the first century, Applejack alone provided the entirety of the continent with food, and enough surplus to share with the world. Now, at the thousand years mark, there was not even a need to work the land outside, as long as Applejack's endless strength kept holding the world.

Twilight couldn't wait anymore.

She stood up and flew over, lading on front of Applejack. Her friend's face lightened up as soon as they saw her, letting go of the giant plow that buried itself in the land from its weight, and grabbed Twilight for a hug. They didn't even try to restrain themself, knowing Twilight could take it. On her part, Twilight was immediately engulfed by Applejack's massive arms. As an alicorn, she towered over every mortal pony, doubling them in size. But that was nothing for Applejack, who tripled her height alone. So, as her friend pressed their naked bodies together, it was like a regular pony hugging a doll.

Being trapped by muscles on all sides overwhelmed. The arms behind her back and on her sides, and the wall of pecs squeezing her breasts and abs pressing her penis against her own abdomen. She tried to move her hips as to rub herself on those abs, hard and warm as inside a volcano. But Applejack held onto too tightly. Until her friend decided otherwise, Twilight wasn't moving in any way. Not that she minded, as she took on the feeling, smelling the sweat of her friend impregnating her. She started to sweat along, followed by saliva an precum. Applejack's immobilizing embrace and giant proportions built the arousal inside Twilight, bringing back her lust.

With a great deal of effort, Twilight slid her tongue out, extending it to better taste Applejack's chest, while also looking for their nipple. When she found it, it was already hard, and almost as big as the apples they grew.

Applejack finally released their grip, sitting on their ass on the wet ground with Twilight -now free to move- resting on their torso. Retracting her tongue back to her mouth, she extended her arms over Applejack's pecs, gently rubbing herself as she looked up. But a pair of huge hands pressed behind her back and on her sides, grabbing her. She was sure that any other creature would have died from the pressure (another of the reasons they agreed to stay in their chamber), but Twilight could take it, and Applejack knew it.

Being handled by someone else, almost powerless as she was brough to he friend's mouth, was a rare experience for Twilight. She was power among her ponies. But in Applejack's hands, she looked like a doll to play with. And she couldn't be more excited about it as her face was pressed against the larger lips. They shared a kiss, Twilight sliding her tongue into Applejack's mouth and drinking their saliva. Twilight lifted her arms to caress their cheeks, needing her whole hands for the task. Despite the size difference, Applejack's short fur and thick skin were still as soft as when they were a pony.

There was another earthquake as Applejack's back hit the ground. Twilight got up, still swallowing a mouthful of saliva. Her stomach was full of the stuff already, making her belly look a bit rounder. Meanwhile, Applejack lied there, extending their arms over their head and crossing their wrists. Twilight couldn't help but shake her head playfully. Under all that unlimited strength and a body so big Twilight could spread open her legs, and barely reach their waist with her ankles, was the bottomest pony she could think of.

Twilight gently sat her knees on Applejack's chest and covered her breasts with arm across her nipples. She enjoyed as her friend's face started to redden, licking her lips as she lifter her other hand. With a flick of her pinky, the earth arose under Applejack's wrists, melting into magma and then solidifying in mere seconds. They both knew that it would take the minimum strength for Applejack to break their imprisonment. But Twilight didn't give them permission, and that all the force she needed to apply on the gigantic enby.

Twilight leaned over, almost as if about to kiss them again. But instead, she opened her knees, pressing her ass on Applejack's chest and putting her hands on the ground between their arms. She poked their lips with her penis and that was all the instructions they needed. They dutifully opened their lips and started to suckle. Twilight had to bite her lip to not moan. But that didn't stop her legs from shaking as Applejack's huge tongue caressed and suckled any precum she could have inside her. She had to actually start using her magic to keep up, pouring a stream inside Applejack's mouth, listening has a throat that could crush diamonds gently swallowed it.

After an hour of no breathing and constant drinking, Twilight stopped holding herself. Applejack's moan vibrated the entirety of Twilight's body as they took her cum in.

She got up from their face and sat back on Applejack's abdomen, her penis already hard and leaking again, covered by a thick layer of saliva. Twilight reached her hands down this time, caressing their nipples. They were so big, she almost needed to use her whole hands on them, once again needing magic to be able to pinch them. Applejack bit their lip to suppress any moaning. Twilight didn't give them permission for that either. Until the alicorn said anything else, the minotaur was to submit powerless to anything the former wanted.

Twilight slowly slide her groin down Applejack's torso, feeling their hard abs caress and tickle between her thighs and under her penis, until she finally felt something wet under her shaft. Twilight released Applejack's nipples, nodding to let them open their mouth and pant from the stimuli, as she got on her knees on the ground between their thighs. She gave a couple of playful slaps on them, and their legs began to part themselves. A flood of juices fell off, making a puddle under Twilight, who was salivating similarly as she saw Applejack's vulva already wet and quivering.

As she started caressing the lips around the entrance, Applejack moaned. In response, Twilight immediately went for their clitoris, caressing the tip with her palm before going down and starting to suck it. Applejack's hooves kicked just a bit, but they kept their legs still for Twilight, who was now pressing her face on their pussy. They could feel that long tongue penetrating them already, masterfully reaching their G spot from memory. Applejack's moans and soft squirming made the earth under them crack. They could barely held themselves as Twilight slowly pulled her tongue out, licking every bit of her entrance and loudly gulping another mouthful of juices.

Applejack looked down, and saw Twilight sitting on her knees, with her arms gently rested on her own thighs. They were panting in anticipation, pleading with their eyes as she waited patiently for the show of submission. They opened their legs the most they could, bucking their hips up and down. Twilight had to admit how much control they had over their body when she saw their pussy opening and closing. The earth and vegetation were disturbed all around them as Applejack begged with their whole body for Twilight's mere touch.

Twilight put her hand over their lower abdomen, just above their groin. That was all they needed to calm down. Then, she slowly got up from her knees and started to press her tip on the entrance, making sure to rub it on their clit before pushing in. She pulled out almost immediately, producing a cute yelp before pushing in a bit more. Like that, she kept entering just a bit at a time, resting her body over Applejack's abdomen. The later tried their best to not squirm, but still shook in anticipation each time she went deeper.

Finally, with a soft 'slap', Twilight's penis was entirelly inside Applejack.

She rested her breasts on their abs, caressing them with a single finger. She then leaned over to lick the muscular hide, burying her face on their body before starting to move. Applejack could feel the heat from Twilight's penis heating their own body, making them sweat like not even the hottest fire nor the brightest light could in the last thousand years. Only Twilight was strong enough to make them feel anything. And that had nothing to do with the power.

Twilight needed to use her whole arms to reach just the sides of Applejack's torso, moving more vigorously as she licked the sweat she knew she was causing. Giving them such pleasure, making them feel it made Twilight feel powerful. In turn, she was leaking all over again. Her nipples pouring a healthy amount of milk where they pressed on Applejack's lower abdomen, her mouth salivating as much as she licked the sweat, and her penis just filling their insides with precum.

Movements, sounds and fluids all shook violently, vibrating the earth to bits as Applejack reached their orgasm. Twilight felt a pressure that could crush a small sun on her penis, which was more than what she needed after so much build up. she quickly got up from Applejack's torso, leaving it soaked in saliva and milk, and began to cum violently inside them. Applejack's insides, already invaded by the previous stream of precum, got overfilled with semen. Twilight hummed as she saw their abs slowly being pushed up by the growing womb. She kept cumming like that, bucking her hips and holding onto their waist until Applejack's abdomen resembled an early pregnancy.

Then, they both fell together, spent from any energy. Applejack, for the first time since the las visit from Twilight, felt tired.

Twilight remained over Applejack's body, releasing their wrist from the volcanic stone and letting them caress her back. She did the same, softly caressing their chest with just a finger, locking eyes together until applejack was the first to be claimed by sleep. Twilight waited a little more, until their arm finally stopped holding her.

She flew up, careful to not wake them up. They looked so peaceful after a good night of sex. She lifted her eyebrows surprised, realizing that indeed it was night. That meant that what she first thought were just minutes must have been hours. A reminder that, when both are immortal and with night unlimited energy, time looses any significance pretty quick.

Twilight silently chuckled to herself, shaking her head from side to side as she used her magic to clean herself and Applejack. Then, needing to use both hands, she heated and melted the grounder under them, letting their body sink in the magma until inly their horned head was afloat. Twilight cooled it again, making pressure with her magic so the rock would be harder to break. Probably just a normal push for Applejack, but Twilight knew they would appreciate the goodbye gesture of waking up trapped and immobilized.

She flew off, opening the door and returning to the center of the Forbidden Chambers. As she exited the door, she started to caress her body again. One visit wasn't even close to enough. Without the spell of Applejack's chamber, Twilight's greed and hunger for lust came back to their fullest, making her unconsciously put a finger inside her lips as she turned to the left, over to the next door.

02. Rainbow Blitz

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Twilight walked over the next door clockwise, to the one marked with a cloud and a thunderbolt. As she put her hand on the stone to feed the magical lock her own power and lust, she took a deep breath and holding it until the door was open. Despite her body needing it, and she just desiring it, Rainbow was intense, and Twilight needed to level herself beforehand.

After the first step into the chamber, everything became a blur. She had to spread her wing to stop what would have been and endless fall. The air currents around her quickly began to push and pull her to one side after another, almost randomly changing directions in an instant. But Twilight knew it wasn't random, it was a pattern so fast and so vast, it as just impossible for most ponies to understand.

She shut her eyes and embraced herself, hugging her shoulder and pressing her arms against her breasts as well as crossing her legs in a new attempt to level herself. She released more of her power, dropping the many limitations she usually had to put on her strength and senses in order to interact with her mortal ponies on the surface. When Twilight opened her eyes, the blurring storm around her wasn't no more. The gale winds became a caressing breeze over her fur, which she welcomed.

Under her hoovering feet there was a line of light and electricity, thick as a road. It extended and split ahead of her, turning into a web of lightning that extended where only her divine senses could really see. She put her index finger on her lips, slightly licking it. Her lust this time came from the surging pride of seeing her work's success. A net of magical energy that spread over across the entire world, reaching inwards to hidden dimensions and outwards to the cosmos. The entirety of the realm she ruled powered by her grander design.

And it just felt too good to look at, knowing it was all hers.

After perfecting the magical absorption with Applejack, Twilight immediately got to work into manipulating so much power. She needed to know how much she could take and, more importantly, command. She still thought like a mortal back then, so she was content with just working Equestria's ley lines, taking power from them in a more refined way than just absorbing their product. But then, she remembered her friends. Applejack was still 'normal' enough to be around Ponyville, but Twilight knew they were far beyond any mortal creature. The idea of only them surviving the rest of their friends was too much to handle. That's when Rainb --

A streak of lightning surged from a ley line behind Twilight and tackled her, turning the world around her into a blur again as she was pushed into another ley line, being carried by the current of sheer power. A pair of hands reached around and across her chest and abdomen, as she felt a toner body pressed on her back. The touch was electric, as well as the air around her. Twilight felt every inch of her body being tickled by the buzzing magic.

For about a nanosecond, Twilight considered opening her wings and releasing herself. For her it wouldn't take more strain than pushing off the bed's covers. But the hand on her abdomen slid down to her penis, stroking her hard as the other hand began to roughly squeeze and massage her breast. That was all the motivation she needed to let herself be taken and carried, as the body pressed on her back began to rub itself between her wings and over her ass.

She hung out her tongue, tasting the electricity as the strokes on her body became rougher and faster. In a blink of an eye, Twilight was mindlessly bucking her hips, feeling the other body behind her moving along, as she was salivating, lactating and precuming. The hand on her breast slid up, pushing a pair of fingers between her lips, which she gladly began to suckle. If the air tasted like electricity, the fingers outright electrocuted her, making her orgasm violently, thrashing and convulsing.

Twilight's wild reaction caused her and her partner to fall down from the ley lines, crashing hard on a terrain made of solid rock. Not that it could harm her or her friend. Neither of them could really be harmed in a way that mattered.

She tried to turn around, still worn from the sudden surge of stimuli, climax and impact. But when she got on her four before getting up, a pair of clawed hands held onto her hips. She could feel the slim and strong fingers sinking in her soft flesh as a hard shaft slid up and down between her cheeks, rubbing just above her anus. It didn't take long before a wet tip started to push into her, stretching her as it made its way in. Twilight took note of the size, clearly bigger than her own penis, as the hands holding over her hips slid up to hold her sides. The tip met her prostate, pressing it down and making her leak again.

The penis inside her began to move, going all the way back to her anus and then ramming all the way in, reaching deeper with each thrust that also became more vigorous as they went on. Twilight let her upper half fall over, rubbing her breasts and face against the stone from the movements behind her hips. She was making a puddle of her fluids on the floor between her knees, trembling heavily. The only thing keeping her up where the hands on her sides that slightly caressed their claws closer to her abdomen, and her own need for more.

With some effort, Twilight planted her hands on the floor and slowly pushed herself up on her four. Twilight her felt partner slid their hands up her body, making her also feel the feathers rustling her as both hands grabbed her breasts. Her partner's body wasn't just electrical, but also hot, turning the air around them light and the stone ground to redden. Twilight was sweating profusely as her partner pressed themselves on her back again, heating her up further.

She reached back to feel her partner, rubbing the feathers that adorned their arms.

"Rainbow..." Twilight whispered.

"Blitz." He finished for her. She nodded in understanding as she let him do as he please with her body.

His groin met her ass, squeezing it as the full length of his penis was inside her. Rainbow Blitz reached deeper with each thrust, making a bulge in lower abdomen. Twilight's sweat began to evaporate as the heat kept rising, especially when his feathered arms slid up and down her body. Suddenly, she felt a rush of heat spreading inside her, overfilling her and making the bulge in her abdomen to grow. Rainbow stood still for almost a full second as she felt the cum getting up to her stomach. It didn't last, though, as he began to move inside her again, this time even more vigorously.

She couldn't hold on much longer releasing another large amount of cum that made a puddle under her body, before collapsing on her expanded belly. His body was a surge of heat and electricity pressed against her back, groping her breasts, making them leak and penetrating her deeper insides. There was a new surge of heat inside her, as she felt it now in her middle and upper torso.

Twilight's body was being filled with cum as she marinated in a puddle of her own fluids over nigh-molten rock, orgasming over and over. Each time he came and made Twilight's body fuller, Rainbow picked up the pace, becoming more aggressive with his movements and caressing of her, also making her cum faster. Twilight stopped feeling the buildup, as her climax became a constant buzzing of her overheated body, filled by and releasing constant streams of cum.

They ended up covered by a thick screen of steam composed of Twilight's own fluids. She could feel Rainbow inhaling the fumes behind her head, feeling hotter from the thought of what were they breathing.

Surrounded by red and white-hot stone, Twilight felt the massive penis finally pulling off her anus, leaving it gaping and leaking out overheated cum that just melted the rock between her legs. She was immobile and spent, not even sure if she could move anymore. But that didn't seem to bother Rainbow, who took her by her shoulders and turned her around. The motion made her aware of how much fuller her body was. Not just her bloated belly as it started, but it looked as if she had gained weight.

Twilight's breasts had grown from a modest to an abundant size. Even her areolas and nipples became wider alongside. Her abdomen, while not massive, now was a round belly, followed by wider hips and a heavier ass. The size spread to her arms and legs, making them twice as wide as she was used to. With great effort, she touched her face, feeling it softer and rounder. In fact, her entire body was softer and rounder as a result of Rainbow Blitz filling her over and over. And she loved every little sensation of it.

In front of her, Rainbow was standing on his knees between her open legs, masturbating to the sign. Like that, Twilight could appreciate better his body. Like Applejack, he had become more than a mortal body, so as time went on, he lost any attachment to it. Instead of a pegasus girl, Rainbow preferred to become more toned and thin build so he could make himself a projectile. The wide wingspan on his back became a colorful row of feather on his arms, ended in clawed hands. Same of his legs, which became muscular with the constant exercise or running forever to generate the magic of the planet.

Twilight couldn't help but notice how much animalistic he became in the last centuries. It was as if his one-track mind only became more focused like a ray of light becomes a laser through a ruby. He was still coherent and had an identity -as fluid as it was, changing from Dash to Blitz periodically-, so she could trust her friend wasn't lost to his newfound power. Another flaring success by applying what she learned with Applejack.

Thinking about how much she made out of Rainbow, and how much the world improved by her hand, made Twilight feel invigorated again without the need of a spell to replenish herself. It did help that Rainbow, no matter the gender, always presented himself as this slim marvel of anatomy and aerodynamics. Twilight could admire him masturbating for years. Specially if the object of his pleasure was herself. He seemed to love what he did to her body, exhausting it and then overfilling it with his own fluids.

Twilight reached down from her face to her breasts, massaging them in wide circles to emphasize their new size, lactating a heavier flow. Rainbow also picked up the pace, massaging his defined abs and pecs while keeping his other hand on his penis, making a sound of rustling feather from both limbs. Twilight reached down, confirming her penis was also larger as the rest of her inflated body. They both kept pleasuring themselves in front of each other, surrounded by the endless stone and ley lines carrying magical energy above them.

Always the rusher, Rainbow couldn't keep himself on his knees and dived down, hugging Twilight's wide frame, and burying his face between her breasts. She hugged back, caressing the back of his head with a hand, and down his back with the other. It didn't last long for him to start rocking his hips, rubbing his long penis on Twilight's wide one. The mix of fur and feathers, of rubbing and caressing made it so there was steam and static around them again.

They came together, slowly leaking from between their pressed bodies down to the floor. They kept at it until they were rubbing on each other over large pool of their own cum they could bathe in.

Being bigger, Twilight didn't have much trouble holding Rainbow, grabbing his arms, and sitting him on her belly. She was licking her lips, looking down at his groin. Not at his penis, still hard despite the marathonic session, but to what was behind it. As lubed as they both were, Twilight didn't have trouble sliding him down, until his ass gently touched her erect penis.

Rainbow looked straight into her eyes, also licking his lips before freeing himself from her grasp. He leaned down, putting his open palms on her wet areolas as he lifted his ass, rubbing himself on her as he slowly lowered it over her penis. Twilight couldn't help but gasp when a small spark of electricity pinched her tip, followed by his hot anus pushing it down. It was clear the inside of Rainbow's was as charged and heated as the outside.

As he massaged Twilight's breasts, he started to move up and down over her penis, pushing harder each time until his tight anus began to open and crowned her tip. As she expected, it felt like taking lava as she felt herself slowly sliding up inside him. She reached for his ass, but he kept pressing her down by her breasts and keeping her straight against the floor. So instead, she settled for caressing his open thighs.

When his anus finally reached down to the base of her penis, he clenched hard over it. Twilight started to moan louder as he followed it by squeezing her breasts, making a flow of milk to come out. He then sat straight, pushing his weight over her penis, and smeared the milk over his abs, then up to his pecs, making his toned body shine. Twilight could only stare with her hands resting over his thighs when he started to masturbate again over her.

Rainbow started to move up and down, making her fattened body giggle as he picked up the speed. Rainbow was so his tight, his insides were outright milking her penis, driving her over to the climax, and barely holding back. Rainbow was still stroking himself as he moved, reaching up to his chest and playing with his nipples. Unlike her, he gladly released a generous amount of cum over her body, spread over her large breasts moving up and down from his movements over her hips.

Despite really wanting needing to taste it, Twilight didn't scoop the cum with her hands or extended her tongue down them. Instead, she kept holding onto his thighs as she held herself back. Rainbow's moans indicated he was close to a second discharge that promptly bather her upper body with more overheated cum. It felt like small flames licking and running down her body, along her sweat. It made her feel wet and hot all over.

They kept at it for a while, each time covering more of Twilight with cum as Rainbow's anus kept holding hard from her penis. They were on a puddle again, him cumming more than the heat from their bodies could evaporate. Until Twilight finally felt him slowing down.

That's when Twilight leaned up and closed her hands on his waist, holding his lower body against her groin. She began to move, not with the buzzing speed he's been using on her all this time, but with seismic trusts that outright cracked the stone beneath them. Rainbow could only grab his face as he felt Twilight ramming herself inside him, reaching deep and rubbing hard. It made him cum without control, but as soon it touched her body, it evaporated with a hiss. It made her smile openly, hanging her tongue to a side and showing her teeth now jagged and pointed.

While she enjoyed letting her friend do with her as he pleased, Twilight couldn't help but also need to take him too. He already had his fun with her, now it was her turn.

She restrained her perception of time again. The world around her picked up the speed, turning the almost imperceptible breeze back to the gale winds that were almost strong enough to make her feel it. But more importantly, Rainbow Blitz turned into a blur sitting on top of him. Twilight moaned again as his anus turned into a constant vibration around her penis. He kept cumming, a full load almost every tenth of a second that only evaporated over her body. She greedily inhaled the fumes, laughing as a pair of blurred hands reached down to her wrist. The touch was merely a vibration.

Twilight salivated, imagining what was it like for him. Every moment of her thrusting her hips would feel like hours of a penis slowly making its way inside him and then slowly retreating.

Feeling such control over someone as powerful as Rainbow was enough for Twilight. She stopped holding back and began to move harder and faster. Slowly, she caught up to him, returning to the same time perception and making it so he wasn't just a vibrating blur for her. Rainbow looked spent and in trance, as if he had been having sex for days without a pause. Which was probably how the relatively few minutes felt to him.

Sliding her hands up his side, Twilight pulled him against her soft and plump body. She cooed while caressing his back again, calming him down as she finally started to cum inside him. The softer stream was a far cry from the quick and violent orgasms they have been sharing, instead slowly pouring herself inside him. She could feel his toned abs giving way to a small bump, and then a belly. Unlike Twilight, Rainbow's body was more resistant to change, he only bloated instead of gaining it as weight like she did.

Nonetheless, Rainbow was full with an abdomen almost as large of the rest of his torso. He burped a bit of cum that reached all the way through before gently falling asleep on Twilight's arms. She kept caressing him, cleaned themselves up before leaving him tucked over the floor of stone they both vibrated into soft sand, still bloated and slowed down for the following years, maybe even decades before he was back at top shape.

Sighing as she got up, Twilight looked up at the ley lines Rainbow had to keep running by running inside them. With him sleeping and later slowed down, it would take for him to push his limits every moment of every day of the following century to prevent them from collapsing. And that was exactly what she wanted for him. To keep having limits to push through in this endless task she gave him. He would become mad otherwise, living a whole lifetime in the literal blink of a mortal's eye.

Twilight walked away from Rainbow, making the door materialize in front of her and leaving him to his imprisonment.