Twilight had some minor concerns about her new ‘toy.’

The first oddity was when she had opened it in her lab. To her surprise, the fibers had congealed into some sort of liquid-like substance, something that shouldn’t have been possible. The familiar sense of magic had come again when she’d opened it. And she’d received another—and much more heady—rush when she’d opened the cube.

After some basic tests, mostly done using her magic, the material grew more and more viscous, again something that shouldn’t be happening according to the alchemical schematics on the bottom of the containment cube’s lid.

Her concern had grown when a quarter through her tests, her magic stopped having any sort of effect on it. She could lift the cube, but when she tried to magically interact with the now-liquid, it seemed to absorb her magic. The magical signature of the liquid grew as a result. Oddest of all, she soon found that the act of interacting—and therefore funneling—her magic into the liquid became rather… intense.

Most concerning, however, was the liquid’s motion.

Halfway through her testing phase, it had begun to move about the room. Twilight had yelped and jumped back at this, but the thing didn’t seem to have any hostile intent. It seemed… more curious than anything else.

Twilight couldn’t help but think about four and a half years in the postal service. Who knew what sort of magics this had been exposed to, containment cube or no? She might be seeing the beginnings of a rudimentary magic-based animal! Perhaps some sort of cousin to the mythical ‘goos’ rumored to inhabit the Hayseed Swamps?

The liquid—the experiment—had wandered over her bookcases. Twilight wholly approved of this, curious if the experiment could actually absorb knowledge. It wasn’t until it had engulfed the bookcase when she realized this was her basement lab bookcases which contained stories that were completely inappropriate for most audiences. Still, Twilight believed it best not to interfere. Instead, she studied it, taking copious notes as she went.

She’d quickly moved to her notebook computer while her desktop continued to process the data she had managed to collect with her various spectrometers and sample analysis scanners. Her hands danced on the keyboard for a good twenty minutes… and then, with startling levels of speed…

It had consumed her desktop computer.

Despite her best attempts, all attempts to pry the experiment from the computer had failed. Nothing she did had any impact. And considering what the thing could learn from the internet? That didn’t bode well. It could easily become hostile if it even looked up the history of Ponyville!

Twilight had hesitated for a good half hour, but in the end she’d been left with no choice but to go upstairs and engage her hazmat protocols.

However, as she had moved toward the stairwell, it had released the computer.

It had laid there for a time, as if considering a course of action. Twilight had glanced up at the desktop screen only to see a lightning-fast slideshow of… erotic images, stories, movies, animations and more? Many of them were… latex-based?

What.

Which was strange as the experiment included no latex in any form. Even if it did remind her of the substance. A little.

She looked up at the computer again and immediately regretted it.

The slideshow moved so fast her brain could barely process it and it began to give her somewhat of a headache, despite its vaguely hypnotic properties.

She took a step forward toward the computer, intending to walk around the experiment to disable the machine so it would stop distracting her from her notes on the experiments.

However, it appeared that the experiment had taken exception to this.

As soon as her shoe hit the ground, it surged forward.

“Ahh!” Twilight yelped, trying to backpedal away, but the experiment grabbed her feet. In the space of a few moments, she had been almost entirely immobilized, both her feet completely encased in lavender fluid. Her attempt to gain some altitude by flapping her wings—which should have been her first response—was pointless. The experiment now had a solid grip on her.

Her breasts bounced as her breathing grew rapid. She knew this was a bad sign. She needed to get help immediately. She lit up her horn to send a message spell to Spike and prepared a teleport spell as a backup. It seemed… yes, Spike first then flee. Right? Right.

She took a deep breath and prepared to shout.

The experiment reacted before she made a single sound. It poured into her shoes, slipped through her stockings and completely surrounded her feet in a thin membrane.

It wriggled along her feet in a strangely comforting sensation, but she fought against the odd calm trying to wash over her. This was not the time for calm. This was the time for panic and quick action.

“Spike!” Twilight called, flapping her wings even harder—all to no avail.

That left only one option. Considering the experiment’s interactions with her magic… she didn’t exactly what to do this, but she had no choice. She unleashed her teleport spell… only for her spell to ground itself into the experiment.

The entire lavender mass shivered.

“That’s… not good.”

Using a strange motion, it slowly shifted her feet until they were parallel with one another. Only then did the strange experiment dissolve her shoes. However, it left her stockings. And it also left her completely unharmed.

She tried to teleport again, but it seemed to just… fizzle.

“Oh, this is bad…” she mumbled. Some of the things on her desktop had been from her own private—very private—archive. She did know how these things tended to go. “Very, very, ba—”

The experiment began to slowly slide up her soft legs, eliciting a squeak from the busty alicorn, which quickly turned into a quiet moan. The experiment didn’t crawl or wriggle but instead moved smoothly as if she were slipping on her stockings in her morning routine.

“What do you…” Twilight began to say only to realize the foolishness of this path. Instead, she shouted for help, but every time she did, the experiment slid a little further up her legs, ensuring that she couldn’t make full use of her voice, as it was marred by her slightly heated moans.

Twilight only noticed that the experiment had moved all the way up to her hips when she felt it begin to pool around her panties.

“No, no, no!” Twilight admonished. “Bad goo! None of that! I… definitely… don’t…”

Something… distracted her. She looked around, trying to figure out what had changed, but… it took her a moment to connect the dots. That should have been another bad sign but at this point… what was one more?

The experiment was doing something to her. She sensed an increase in blood pressure and heart rate. Her nipples hardened. Her sex grew damp. She… the experiment was arousing her! That… that was impossible!

But impossible or not, it was happening. It began to slide up and down her hips and buttocks, not to mention her front, though it did not invade her most intimate place. Instead, it attacked everywhere else, from all sides. It stroked her thighs and the tiny little erotic spots on the arches of her feet Spike had found about a year ago when they’d both been drunk.

Then it slowly dissolved her stockings. However, the sensation wasn’t one of destruction. No, the experiment simulated the feeling as if they were being slowly pulled off by somepony… using their teeth.

Twilight let out a lewd moan and, with the increasing movement and delicate teasing, instinctively spread her legs a little. To her vague surprise, the experiment let her, adjusting the position of her feet to make her comfortable.

And then it slid into her panties.

Twilight groaned. She knew this was a ploy. She… she…

“I… shouldn’t… let…” she panted. “I shouldn’t…”

She could feel the experiment cupping her mound. It undulated slowly, massaging her in a way no lover ever could. The experiment continued to work on her legs, her feet, her thighs and her mound, seemingly content to heighten her arousal by the second.

She… knew better. She was going to resist and figure a way out of this. She wasn’t going to end up some goo’s sex toy…

It wrapped itself completely around her hips and waist, save for a very noticeable empty spot. Then, it subjected her to a full-lower-body massage.

“No, you’re… draining my… resistance…” she whispered as a hand drifted to one of her heavy breasts. “Seducing me…”

The experiment, of course, made no reply. It just kept working at her. Twilight fought, but the longer it had her in its grasp, the more it began to learn about her. Twilight could feel its discovery of her lower body’s erotic secrets. The points she had learned through extensive experimentation—either by herself or with another. Each point would cause an increase in pleasure. Sometimes, a substantial increase.

“Spike…” Twilight moaned, looking up at the door to her lab. “Come… come save… me… or…” She whimpered. “Or come fuck me… fuck me again like you did on Sunday…”

Her hips bucked and her tits bucked with them. Her wings stretched despite her… stupid traitors.

The vibrations on her mound increased.

Maybe that guard could help her. Maybe Flash Sentry might be of use. A spell to increase virility, an extended period of intense sexual activity, then perhaps a spell to turn him into a lusty mare like her. One that would eagerly lap at her experiment-covered pussy as Flash was overcome by the same transformation that had claimed her. After all, Flash had already spent some time as a mare. Twilight would make out with the hot mare as they surrendered to…

The vibration increased again.

Her thoughts became increasingly jumbled and addled. In some part of her mind, she knew this, but at this point, she found she didn’t much care.

Spike would be next. The two mares would descend upon the handsome drake. Twilight had enjoyed Spike’s draconic cock on occasion. After all, they were best friends and he was now a foot taller than her. Twilight would make out with the drake as Flash… Flare, perhaps? Flash would need a new name within the Bond—whatever that was. Flare would lap the drake’s cock until it burst in her mouth. Then Spike would fuck Twilight for the last time. When Twilight came, her gift to him would grow over him, making them closer than ever. Spike would retain his dragon cock as needed to fuck Flare and herself, but usually, he would be in the form of a female. Creatures within the Bond couldn’t help but think of themselves as female. She…

She… shouldn’t be thinking like this… she should…

Her own moan snapped her out of the silly thoughts as a finger teased her sex.

One of her hands was in the strange lavender liquid, fondling her sex. But when she pulled her hand away… it remained clean. Odd. Most times… most things she’d seen showed it would strike at a moment like this. They used any chance they could get to spread.

This one didn’t.

Had she misjudged the experiment’s intentions?

It… didn’t seem to be affecting her mind. Maybe…

She idly ran a hand along a tit… a breast. She didn’t use terms like ‘tits.’ She was more educated than that. And an educated mare always wished to share her knowledge.

Perhaps the experiment only wanted to experience something akin to sexual intercourse. It would make sense considering what it had accessed on her computer. She did have a great deal of… research material on the subject.

It’s seemed possible. No, not possible. Probable.

Yes. That was it. She should spread her legs for it, to give it the chance to experience the pleasure of copulation.

It thrummed against her mound.

She felt tickles of something against her back, sliding up and down her spine. It felt amazing. She idly wondered if the experiment could use her spine as a… a…

Yes. It now seemed perfectly logical. All it wanted was to experience intimacy and passion. It had read these things, but had no framework. It had been her material. It was only fair for it to gain that framework from her.

The intensity of the vibrations threatened to overwhelm her into a mind-shattering orgasm.

Since the experiment had behaved so well, it deserved to experience this with a willing, unaltered host.

Yes. Yes. This was… yes.

Twilight felt something click in her mind. She relaxed and sighed, smiling as—

The experiment suddenly poured into her sopping wet pussy. Twilight screamed in delight, her hips bucking wildly as she came on the experiment… no… that wasn’t the right word anymore. That felt wrong. It was rude for something that knew her so intimately. It deserved a better name.

“Companion,” she whispered to herself as her hips bucked.

Companion shivered inside of her, sending trembles through her aching core. She could feel it filling her to the brim, pouring through her pussy, even slipping through her cervix and into her womb.

Twilight squealed as she felt her belly swell with Companion’s essence. She thrashed and groaned, barely able to think as she frantically fondled her suddenly sensitive stomach. Then, Companion got better situated within her.

Twilight moaned, holding her stomach as it shrank back down as Companion evolved and changed. She loved the sensation of it moving over her, filling her, changing her…

Changing her? Wait, that wasn’t—

It wasn’t changing her. It was being what she wanted it to be. Yes. What she needed it to be. To experience sexual copulation, of course.

No, wait… the Companion didn’t serve her. She was serving it. Why was she getting so mixed up?

Her brain-bending orgasm had just been an adjustment to Companion getting in position to experience this new sensation. It just took a little time.

In fact, in that time, it became better situated by becoming a thick dildo that slowly began to slide in and out of pussy.

She moaned.

“Thank… thank you, Companion,” she whispered.

To her surprise, her naked feet were free now… though… she knew she had somewhere she needed to go in a hurry. But she couldn’t remember where.

After all, why would she want to leave?

It probably didn’t matter. Companion agreed, showing her its opinion by the increased thrusting of the dildo.

She glanced around the lab, moaning constantly. Companion likely wanted her to relax more, but she didn’t even have a good chair in here, just a boring stool for her computer. That wouldn’t do.

What she needed was… was… a bed.

The fucking increased. Companion approved. She could teleport herself or conjure a bed down here.

Her panties dissolved in a rush. Their disappearance felt like a lick from a giant tongue against her hot sex.

Now she really needed a bed. She wasn’t how much longer she could hold herself… hold them up…

Without thinking, she conjured a bed near the containment cube where Companion had been born. It fucked her slow and soft, showing how much it approved of her actions, encouraging her to continue.

The aftershocks of the wonderful lick lingered, reminding her that she didn’t wear panties. Panties got in the way of pleasure. And she adored pleasure. So no, she had never worn panties. That way she could…

“I feel… strange…” Twilight mumbled. “I feel… horny and sexy… no, strange…”

The dildo almost stopped when she spoke about feeling ‘strange.’ But Twilight didn’t want Companion to stop. She needed to encourage Companion to continue.

“I feel so horny and… and… hot…” she said hesitantly.

It was an obvious statement of facts, but Companion demonstrated its approval.

She looked at the bed she’d conjured.

“I should get into bed to let Companion fuck me better,” Twilight whispered. “I should surrender to… to…”

The thought slipped away. She couldn’t remember who she wanted to surrender to. She’d been so sure about things earlier… why…

Her legs began moving as the dildo pumped her vigorously. She couldn’t stop herself from moaning and fondling her tits. She wanted to pull off the rest of her clothes, but Companion liked to remove them… though she didn’t know how she knew that.

She settled on the bed in a strange, jerky motion. Then, she slid atop it, lying face up. She spied the door and without a second thought, locked it. It was against experiment procedure, but she needed private time with Companion. Anyway, she didn’t have any active experiments. It was only Companion and her down here. She didn’t want to be disturbed as Companion completed her education. Or… was she completing its education? She…

She blinked. Did it matter? She was already learning so much. She needed to learn more. She loved learning. She started to think about her education… and realized that perhaps she had been neglecting an aspect of study. One that Companion could help her with. That sounded right.

Companion approved of her actions and thoughts in two ways. First, the dildo thickened inside of her, and then it began to slip up her body. Twilight let out another piercing moan as Companion consumed her up to the belly button. Only then did she really feel it cup her ass. It began to massage her, but the motions were hampered by her lying on her back.

“I should turn over so Companion may alter me to align with its directives,” Twilight said, though a moment later, what she had said had already vanished from her mind. She frowned. She was rather forgetful today. She should…

Twilight turned over. The dildo that lived inside her pussy shivered as she pushed herself up to all fours. Her tail swished around, twitching back in forth in desperate arousal. She turned to look at her tail and behind… then gasped as her behind actually swelled outward. Companion continued to fuck her, but the change itself was intensely pleasurable, even more so than Companion’s forever-fucking rod. She watched in shock as her rear continued to expand until it became the size of Pinkie Pie’s!

“Oh… oh my…”

More lust-ridden fantasies played across her mind as Flash Sentry and Spike took turns enjoying sex with her, constantly thrusting and bouncing off of her impressive rear. Their hands—or claws—gripping it in passion and—

She let out another moan as Companion went into vibration mode while it decided to explore her tail. Tails weren’t normally erotic, but at present, Twilight was having trouble thinking of anything that wasn’t erotic. She whimpered and thrashed as Companion slowly and sensually claimed her tail, down to the last hair.

Her body flipped over again, though this time, she didn’t remember wanting to. But that didn’t matter, for her hips were swelling too. She ran her hands along her swelling sides, growing full child-bearing hips. Hips that encouraged potential males to fuck her.

That’s what she wanted. She was pretty sure of that, at least.

Oddly enough, she couldn’t feel a difference between her lower half and Companion now. It was almost as if there was no difference. As if her body was now made of the same latex-like material as Companion. But that was foolishness, as Companion only wanted to experience extended sexual contact with her, not change her on some deeply biological level.

Companion’s thrusts became slow and deep. Twilight spread her legs for it. Was ‘it’ even the right term anymore? It seemed impersonal. After all, Companion was essentially making love to her in the most erotic, passionate and intimate way she’d ever experienced in her life. It deserved a proper pronoun, such as ‘he,’ for it was obviously masculine.

Companion thrummed. She wondered how he reacted to her thoughts in addition to her words, but—

Companion slipped up her body further. Twilight screamed in pleasure as he crept right up to the bottom of her breasts under her thin white button-down top. He had ignored her skirt when it had taken her hips. Companion gently prodded at the clothing, as if asking for permission.

Twilight giggled, positively giddy. She had the kindest, most considerate lover coating her from the inside out. She moaned quietly.

“Strip me,” Twilight whispered as her hands slid across Companion—and her—wonderfully tender skin. “Make me your playground…”

A single hard thrust of affirmation told her exactly what Companion thought of her words. She let out several horny cries as Companion dissolved her skirt, then proceeded to remove her top and her bra. With each removal, Companion always created the sensation of a physical lover being present, slowly undressing her in the most erotic fashion possible.

Then, Twilight lay in the bed, stark naked, coated in soft lavender material not unlike latex. She gripped the sweaty bedsheets as Companion continued to pound into her with strong, powerful thrusts, making her his. She wanted this so badly. In fact, she wanted more.

“Take my tits,” Twilight whispered.

Companion did not surge this time. This time, he lovingly teased his way beneath her heavy breasts. With his surface, he kissed the underside of her assets, eliciting moan after moan from the horny alicorn. Only when every part of her underside had been loved did he move up, sliding up her wide surfaces, though avoiding her nipples at present. Quickly, Companion claimed her up to her neck, leaving her splayed wings, her arms and her nipples still exposed.

Twilight didn’t want to be exposed. She wanted Companion to claim these parts of her. She wanted Companion to claim her entirely. After all, he deserved it. She’d offered herself as his test subject. She wouldn’t be happy until he had thoroughly tested her.

Yes. That was right. She couldn’t remember the details, but that was right. She had offered her body as a sexual test subject for Companion.

“Take my nipples, please!” Twilight begged. “They’re required for a full test!”

Companion decided to have mercy. He gently flowed over her nipples… and then flowed into them.

Twilight screamed, more from surprise than actual pain. A few seconds later, she was once again twitching and moaning in pleasure as she felt her milk glands being converted to serve the needs of Companion. Something she was more than willing to do, in the interest of science.

Her mouth locked open in a soundless cry of pleasure as Companion made her burst with lavender milk.

It felt so wonderful to have Companion inside her breasts, altering her. Changing her. She wanted to be changed. For science, of course.

Soon, they had swelled slightly in size as Companion finished his changes to her breasts. She felt proud of her new size. It would help Companion attract more test subjects for seduction and conversi—

Twilight blinked, suddenly losing her train of thought. She attributed it to the nonstop sexual bliss she’d been in for an indeterminate period of time.

Twilight began to fondle her Companion-covered tits, but this time, Companion did spread to her fingers and hands. She eagerly welcomed his touch upon her extremities as the two lovers became even closer. She squeezed her large tits together with her Companion-covered hands and moaned as the two giant titties swelled in size much the same way her rea—ass had.

There was nothing wrong with being a sexual creature. And she was, so she should use proper terminology. Like titties, ass, pussy and more.

Companion caressed every place she thought in approval.

She moaned when a second flood of a lavender substance that seemed similar to Companion’s composition poured from her erect nipples.

She shuddered as she felt her Companion’s touch on her arms connect with the part of him on her shoulders, leaving her completely encased her save for her wings.

She spread her wings fully, feeling so deliciously submissive as she did so.

Companion began to gently and sensually wash over every feather, but as it did so, Twilight sensed Companion wanted something of her. She sensed…

She felt an odd tickle against her neck. She rubbed at it, only to find a small tendril reaching up into her hairline. She hesitated, tracing the tendril through her mane until touching her temple and… she didn’t need to worry about that.

In fact, the thing that had been slightly concerning from her was removed from her mind a few moments later.

She needed to go to the computer.

Author's Note

Honestly, I never had a thing for this kind of TF until recently when I came across a ton of super sexy art about people getting TF'd in all sorts of ways~! (Mostly by going through e621.net and checking the transformation tag :3 ) It's so great~!

Also yeah, in this anthro world, ponies have the interwebs. More fun that way~! Even ponies gonna have pron. :3

Lemme know about mistakes in PMs, cuties~! <3