Jack(assing) Off

Story by Gabriel Moon on SoFurry

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#114 of Commissions

A man, enjoying his jackass-sized sex toy, fails to read the label and finds out that its tempting use has unexpected and transformative consequences


Geoff stared at the small, cardboard box with trepidation, wondering if he'd dare open it. He really should; with the amount that it had set him back financially, he'd be a fool not to use it. But a part of him, a more rational part, was a little put off by the idea. What would his family and friends think of him for using such a thing? He'd never let them find out, of course. But, what if...?

Years of lurking on websites exploring the furry fandom and the idea of transformation had brought him to a service that specialized in sex toys for those who shared his interests. A few clicks and some customization later, his purchase was ready.

Geoff stared in wonder at the replica donkey cock sitting wrapped in the box. It was specifically molded to fit over a cock of his modest size. He was promised a comfortable fit and an amazing tactile experience when stroking himself off with the new toy.

The sight of it was instantly making him hard. He'd always fantasized about having a massive jackass-sized member between his own, wondering what it would feel like to stroke off with a donkey-sized cock. Racing against the oncoming changes to finish before he lost his hands to hooves and brayed for real, ending up on all fours as a true ass.

For the most part, he did not truly wish to trade his humanity for an asinine existence. But the thought of such a change made him powerfully aroused. He blushed a little as he realized even now how powerfully hard his member was at the thought of stroking off with this toy.

No one was expected to come by his place any time soon and he had no additional work for the day, leaving him free to enjoy the toy as he wished. Looking at his phone, he made sure to leave it on silent before setting it down across the room. If he was going to do this, right now, he would do it with no distractions.

Geoff could feel a slight breeze coming in from the front door where he'd left it open but paid it little mind. It was hot in his new house and he needed to allow the airflow. And besides, he would be in his bedroom upstairs with plenty of time to get his stuff put away if someone came in unannounced.

Geoff took the box and all its contents into his bedroom and pulled out the little pamphlet that came with the toy. There wasn't much written aside from some simple cleaning instructions and some information about the maker and the material used. However, something caught his eye. In large letters on the back was a thickly printed warning.

He took a moment to pause and read the disclaimer that had come with his new toy. He had expected the usual, wash after every use, don't leave it in direct sunlight, don't expose to certain chemicals, that sort of thing. However, the warning that came with his toy was a little disconcerting.

'Use only for brief periods of time. When finished, place the device in safekeeping and do not use it again for at least two weeks. If urges persist, please seek medical attention. Over-usage could result in irreversible changes. Contact our website for more details. Our company has designed this toy for your experience to be as life-like as possible. If you do not wish to make a permanent change, please heed the above precautions.'

Geoff was a little perplexed by the words but nonetheless stripped out of his clothes and took the sex toy in his trembling hands. He applied some lube gently to his already semi-erect cock and inside of the toy for good measure. He stroked himself a few times, imaging that this cock was starting to grow from his more modest human member. Once he deemed himself hard enough, he slid his prize over the tip of the cock and gently down over the length of the shaft.

A gasp escaped his lips at the startling pleasure emanating from his cock. It was like nothing he could have prepared himself for! Not only was the toy form-fitting, covering his cock like a glove, but the sight of a fully asinine member protruding from the base of his cock was like a dream. He could feel his fluids leaking from the tip and mingling with the lube he'd already placed inside the makeshift cock. Geoff's hand was on it in an instant, gently stroking up and down as the waves of pleasure radiated over his body.

Geoff began to envision himself changing as he stroked his new length. He imagined what it would feel like to have tiny hairs pickling all over his balls. To feel his tailbone ache with the promise of a new tasseled tail. To feel his balls swelling up with thick donkey seed. The images were especially vivid with the sight of a massive donkey cock sticking out from his crotch. He wasn't going to last much longer with these fantasies playing out before his eyes!

As he stroked, he was barely aware of the subtle changes to his body. His tailbone felt a little sensitive as he rubbed it, but he simply played it up to his imagination. He felt an irritating itch along his neck but did not want to remove either hand to scratch. His balls ached as well, swelling with seed as the skin began to discolor.

All of these changes went entirely unnoticed, however, as he rubbed his donkey dick more frantically now, having gotten used to the feeling of the toy over his own cock. He could feel his member swelling inside the toy as the powerful images of his transformation played over his mind. He had wanted to hold out a little, to enjoy his first time, but the desires were too powerful, and it had simply been too long since last he'd cum.

"HAA...FUUUACCK!" he yelled as ropes of cum sprayed out of his cock and leaked over the open tip of the toy. He lay panting on the bed as he watched a pool of offwhite seed leaking out of the flared tip towards his open palm. Geoff could smell his spunk and sweat but he didn't mind. He hadn't had a wank this good in ages!

He lay on his back for a few moments, savoring the relief that flooded over his body. His other hand finally free, he was able to scratch at the annoying itch on his neck, just below his hairline. He noticed the hairs on the back of his neck were a little longer than he recalled, but he had to admit he liked the feeling. 'Kinda like the beginnings of a donk mane' he thought to himself. Still, he made a note to ask his barber to be more careful about getting that area next time he went in.

Getting up slowly, Geoff went and carefully tended to his toy with cleaner and washed it in his bathroom sink. As he did he scratched ideally at his groin, just now noticing how hairy he was down there. He made a note to shave tonight when he took his shower, though the thought of having extra hair like a donkey was slightly arousing on its own.

Placing the toy back in its box, Geoff stored it away in a secret place where he was certain his parents wouldn't find it should they come to visit. As he bent over he noticed the soreness on his tailbone once more and reached back with his hand to try and alleviate it. His seeking hands felt a noticeable bump, as though he'd hit it on something. Perhaps when he'd been touching himself? 'Maybe it was a tail starting to grow', he thought with a chuckle.

The area just above his spine did feel very sensitive, to his delight. He moaned a little as his exploratory fingers played over it, noticing for the first time a swash of hair that hadn't been there before. He smiled at the thought. Body hair was super sexy, making him think of a change towards a more asinine body that frequented his dreams.

He bent down to pull on his underwear, noticing for the first time how plump his balls looked as he tried to cradle them in the confining fabric. Eager fingers played over the hairs once more. His dark-skinned testicles seemed covered in a light layer of fuzz that made Geoff moan. And they were so big! Even the massive orgasm he'd had wasn't enough to fully empty his weighty orbs. He liked the sight of his balls and fuzz, feeling more virile and masculine than he'd felt in a long time.

Once more, Geoff felt himself grow hard from touching the increasingly-manly physique he'd been blessed with. How could he not? Naughty thoughts started drifting towards the toy in the box. It had not been for more than 20 minutes since he'd cum but he was ready for another round. Geoff hadn't been this horny in a long time and he welcomed the arousal!

As he pulled out the toy the very stern warnings he'd read on it slowly came to mind. He had no idea what they meant, however. He was sure he was going to get a little chaffed if he touched himself too many times, but that was it. And he'd cleaned and dried his toy properly. The more he thought of it, the more the idea of putting on the toy and touching himself again became intoxicating. His cock was already leaking copiously into his shorts and his balls were throbbing with the need to be emptied.

Being a little less wary of using the proper amount of lube, he gently pulled his donkey cock out of his box and placed the base over the tip of his shaft. Geoff grunted as he slid it over himself, feeling it was a little tighter than before. He realized he needed to use more lube next time, though it still felt amazing over his cock. If anything, the sensations were more intense as he began stroking himself, once again enamored by the sight of the equine phallus where his own once was. It was such a powerful aphrodisiac!

This time, as he eagerly tugged at himself, Geoff could feel his ears tingling slightly, and he imagined them growing thick and long and sprouting gray fur as they arched over his head. He pictured himself opening his mouth to let out a confused bray and he did so, grinning lewdly as he imagined himself mid-change. His fake donkey noise caused a spurt of pre to drool out his cock. He could almost feel the pointed ears growing a fine layer of fuzz, as though his bray was a catalyst to actual change.

Lost in the fantasy now, Geoff imagined himself finding out he was to be a donkey forever, doomed to an asinine existence. The sight of his changing cock made his testicles twitch and throb as though they were expanding. He played a finger underneath them, teasing his fuzzy balls as he moaned and leaked into his toy. He imagined them growing plump, thickening into weighty massive black orbs filled with jackass sperm. He could almost feel them growing at his prompting as he continued to stroke himself off.

The tingling on his tailbone returned with a vengeance, and Geoff was once again reminded of the sensations of sprouting a tail. He imagined feeling his ropey length stretching over his underwear and wriggling in anticipation of his oncoming orgasm. He could almost feel the wriggling above his ass as his new tail was birthed from his spine. What he perceived to be phantom tingles of desire were almost real!

He was getting so close, the mental image of becoming an ass powerfully arousing. Geoff reached back with his one hand to play along his taint and then further up towards his asshole. He wanted to rub himself a little, to imagine his asshole growing thick and puckered into an equine donut.

To his shock, however, he couldn't find his pucker! Geoff slowed his frantic strokes a little, wanting to wait to finger himself as he came, but his pucker was nowhere to be found. He tried to hold back the pressure growing in his cock as he reached around the area, his tail hole seemingly missing. Clenching it a few times in an effort to locate it, the sensations seemed dislocated. Reaching his searching hand, to his horror, his fingers easily slipped inside of the now-massive asshole that was planted higher up towards his still-aching tailbone

Despite the feelings of pleasure, Geoff was determined to remove his fingers from the bizarre sensation in his rectum. But no matter what he did, his asshole seemed to suck them in deeper, making his prostate throb against his balls. He wanted to fight it, to figure out what was happening. He couldn't really be turning into an animal, could he? Such things weren't actually possible, as much as he would like them to be. Then, what could explain what had happened to his anus?

Geoff felt he had to stop touching himself and take stock of his body. Yet no matter how much effort he put in, his fingers wouldn't stop stroking his cock. He was so close already, and the stimulation to his anus was all he needed to send him over the edge.

"Oh...it's cumming...fawwwwwck!" He yelled, a truly asinine sound this time as he came harder than before and shot spray after spray of stinky cum out of the tip of the flesh-light. He shook and vibrated, terrified by what he might see when he finished. But he was so powerfully aroused by the prospect of change that he lost himself in the exquisite orgasm.

Geoff came down from the orgasmic high shortly after, laying in his bed and panting. Yet, quickly, he felt a bizarre pain under him and rolled over, the horrific reality of what was happening hit him like a ton of bricks. He had to move so that he wasn't crushing his growing tail. His donkey tail!

Geoffrey sat there on the bed in shame, terrified to look in the mirror, not wanting to see what else had changed. It was a near-impossible task to separate his fantasies from the reality of his situation. He had imagined so many of the possible alterations. Which ones were in his head and which were happening to his body as a consequence of his heedless ignorance of the box's warnings?

Knowing he needed to bite the preverbal bullet, Geoff slowly got up, staring in trepidation at the light peppering of grey hairs and the pointed fuzzy ears he had sticking upon his head. A closer inspection revealed that the hairs were still growing, thickening into a gray beard that would soon be a full-fledged donkey fur coat if they didn't stop. Even ceasing the use of the toy wasn't enough to stop the changes that seemed to still be working their way over him. How was this happening?!

Bracing himself, Geoff turned around so his ass was visible in the mirror. He stared in shock as an inch-long tail stuck out of his backside. But it was worse than that. His entire back was covered in those same damned gray hairs. And his ass...the thickly muscled black pucker had indeed moved itself to be below his tail. His ass was fit only for a simple farm beast!

Shaking his head over and over, Geoff tried to rationalize what the hell was happening to him. People didn't just randomly start turning into jackasses, after all. It had to have been that damned flesh-light! He'd always wanted to imagine himself changing, but he never wanted it to happen in real life! He couldn't imagine himself being a stinking farm animal, living in a barn and rutting with other beasts! He had to stop this before it got any worse!

The first thing to come to mind, Geoff tried in vain to call the number on the box. There seemed to be a hotline for instances where the toy went awry, but the voice messages were all very rude. The warnings had been on the box, after all, went their logic. Yet how was he supposed to know the consequences of not following them? Even worse, how could he have known it was possible to turn into an actual fucking animal?

Finally, he got through to a service hotline operator, and after exchanging a barrage of angry words and frustrations, Geoff was directed to a series of automated responses. His 'condition' was an unintended side effect in some individuals. The changes would go away if he didn't use the toy or touch himself at all for a period based on the number of orgasms he'd already had. He'd just have to wait 48 hours and then not use the toy for another month to be spared an asinine fate.

Feeling a little relieved from learning about such a simple solution, Geoff put the toy away, secure in the knowledge that the changes would eventually reverse if he didn't use it again. He could call off a few days of work to let himself unwind and start to slowly change back. It would be OK, no more than a strange nightmare. Or a pleasant dream, if it hadn't been happening to him in real life.

Geoff began his nighttime routine, wanting to turn in early after his eventful day. Yet the more he went through the mindless motions, the more a sudden ache in his cock beckoned to him. It had felt so amazing to cum seeing a donkey member hanging where his own was. No masturbatory experience before, or likely since, could compare with the pleasure of using the toy over his own member, magic curse or no.

As insistent as they were, Geoff tried to distract himself from those intrusive thoughts. He'd been warned by the hotline that any sexual activity, with the toy or without, might exacerbate or even accelerate the transformation. Not wanting to change all the way, of course, he would have to wait until the changes had completed receded before touching himself at all.

Geoff had been fine with that at first. He didn't often indulge himself in the pleasures of the flesh and after the massive orgasms he'd experienced today he was sure he'd be satisfied for at least a month. Yet as he reflected on his changes and the experiences surrounding them, he couldn't help but get horny once more. His cock sat uncomfortably tight in his pants as his mind kept drifting back to the feelings he recalled from masturbating with an equine cock. It had felt so good, just imagining himself changing, the temptation of being a simple beast and able to give in to his lusts whenever he wanted.

Without realizing it, his cock had hardened and grown beyond the confines of his underwear, pushing them away as it climbed upward. It was bobbing back and forth on his chest, slapping against his stomach from something that had pulled from his former foreskin and attached itself to part of his rounder belly. Awareness of its presence on his body only came to his mind as he reached down to subconsciously touch it, fingers brushing against a tip that was out of the confines of his clothes. Though it remained human, for now, its size did not match the penis that Geoff had after the last time he'd used the toy.

Blood running cold, Geoff began to panic as he realized his changes were beginning once more. He kept his hands firmly to his sides, lest he was tempted to orgasm. Yet the sight of such a beastly appendage sticking out of the waistband of his pants served only to fuel his arousal. Worse, the feral scents wafting from the flattening tip began to erode away at his resolve. And that was not the only thing to alter, Geoff able to feel every inch of his changes sweeping over him, enhancing what had been done to him prior. His tail beating at the insides of his underwear, begging for release. His mohawk prickled the skin above his neck, getting thicker as it grew between his steadily pointed ears.

Despite all efforts to will it down, his cock was leaking like a faucet now, staining the outsides of his shorts. He tried to fight it, to hold back the lust and arousal. But it felt as though every drop of pre that leaked from his needy rod carried with it a sliver of the realization of why he had been fighting. It felt so hard to focus on why not to touch it when he had such a bestial appendage that demanded his attention.

Worse, every prickle, every tingle of change only served to turn his focus to the sensual feelings centering on his cock. He could feel his glutes expanding, new muscle rubbing the bare skin against his entrapping garments. His balls swelled a little more, full of thick virile jackass seed. The feelings of them brushing lightly against the insides of his underwear were enough to make his cocktip leak further. He buried his arms in his pockets to try and resist the temptation but Geoff was beginning to forget why he bothered, lost in a lustful haze as he was.

Arms were still firmly planted at his sides in a final act of defiance but it was of no use at this point. As if in response to his needs, his cock surged forth with a rush of blood and sprang all the way out of his new sheath. Already the tip was beginning to flatten, the skin along the shaft turning a mottled black as it swayed back and forth from his lusts and the sheath that kept it attached to his distended belly.

All the while, the changes continued to enrapture his mind, every mental protest met with the dissolution of his human thoughts like seed into his waiting balls. Each tingle signaling the expansion of his ass. Each twitch of muscle filling out all over served to enrapture his senses. Geoff was aware of every sensation from his new hide, every patch of gray fur that began to erupt from his pores. Every inch that his donkey tail tore out of his hindquarters. He was even aware of how his hands, firmly trapped in his pants, were thickening at the ends of each twitching digit, the nails turning brown and muddied.

Too late, Geoff realized that his cock had been bobbing against the sheath on his stomach, and the sight of such a bestial act in tandem with the changes had all but brought him to the edge of orgasm. Geoff tried to stop but even the slightest touch of his thick nailed fingers was all it took to force his inevitable end. The orgasmic shock wave reached down to his balls and sent the signal of an orgasmic eruption that he could not stop.

"FFAAAAWWWWCK! HAAWWWWW!" Geoff cried out as his shaft shook violently and sprayed his bare hairy chest with rope after rope of donkey seed.

Panting intensely from his third release of the day, Geoff was dismayed to find it left him no less horny. It was as though each release simply caused his balls to enlarge, each human worry was dissolved into the semen that would fill them to the brim once more.

Not wanting to be needing to know all the same, Geoff looked down at his changes in shame. It was increasingly obvious there was nothing he could do to stop it. Now he had to live with the guilt of knowing it would take twice as long for the asinine changes to even begin to recede. He would have to call in sick to work long-term. He couldn't be seen in the human world like this! There was no place there for the beast he was becoming.

Eventually, Geoff got into bed, trying to put the memories of the day behind him. Yet his bestial desires were even creeping into his dreams. He dreamt of fields of grass and hay, of jacks and jennies both, any lusty beast that would help him quell his own needs. His churning balls pumped out load after load of donkey cum, permeating the mattress with his equine stink. It was as though his internal desires removed the tiniest bits of humanity from Geoff's form each time, as though prepping it for eventual equine perfection.

Geoff awoke the next morning to a rank stench in the air. It was pungent, thick, and heady, clearly that of cum that was not his own. But the deeper he sniffed, the more he realized the scents reminded him of self, of herd, and they began to relax him a bit. Almost reflexively, his cock slowly slid out of his sheath just a little, a sign of his contentment. Even with all the times he had cum in the night, it seemed his changing body still had more to give.

Geoff rolled out of bed, muscles feeling stiff and sore somewhat from the events of the past day. Yet, instantly, he tumbled forward, realizing that his heels no longer touched the ground. It was a painful reminder that if he could not stop the changes, then they never would again. His feet made an odd click on the floor as he walked, and he looked down to realize that his middle toe was thick with a hard nail, while his other toes seemed smaller and no longer touched the ground. In fact, he quickly found he was able to balance his entire weight on these single hooved digits. The horror was plastered on his face as he discovered he was on his way to possessing a full set of donkey hooves!

The nighttime changes had not stopped there. His hips were wider and jiggled a little with added mass as he walked. His balls ached from being so much weighter, heavy on his form from their gravity against his two-legged stance. His stomach was distended, thicker in some places with smelly, sweaty hide as patches of gray hair over his skin. His chest had barreled, making it harder to move his arms around the way he was formerly accustomed.

Perhaps the most prominent feature, however, was the new additional length to his ropey donkey's tail. When he'd fallen asleep it was only an inch or two out of his spine. But now it swung lazily behind him, 8 inches now and tickling his black puckered anus with the growing tassel. When he focused, he could move the thing, like a new extension of himself.

Curious, Geoff rubbed at the base, moaning from the erotic sensations as he stroked up towards the tip. He could feel soft furs spreading up the warm appendage as he wrigged it back and forth. He couldn't believe how wonderful it was to explore and play with a brand new extension of himself. He'd always wanted to have a tail, to feel it stretching out of his spine, growing with each touch of his thick nailed fingers. It was everything he'd dreamed of, feeling the ropey limb expanding longer and thicker as he began rubbing up and down from the base.

Completely enamored by the growth of his donkey tail, Geoff failed to notice his cock once again slithering from out of his sheath. The stimulation to his tail placed the bare amount of pressure on his prostate, making his ample, orange-sized balls swell and his shaft beat against his distended stomach. He had no idea he was masturbating as an ass would, cock rubbing against his stomach and feeling his balls dangling as they swelled. Unaware of anything but pleasure, he continued to grope his tail, enjoying the feeling of gray hairs poking around its length, how gripping the base made it grow longer, faster. He absolutely loved the look of such a beastly thing attached to his backside!

Geoff was so enraptured with his new appendage that the orgasmic release caught him entirely unaware. "HHAAAWWWWWWWW!" He brayed, a truly asinine sound as his slapping cock sprayed a thick load all over his hairy chest. The stimulation to his sensitive tail was more than enough to bring him to climax.

Yet, the release soon brought with it a deep sense of disappointment with himself that was too much to bear. Afterward, Geoff sat on the bed, yelping as he nearly crushed his new tail, the object of his equine shame. He couldn't believe he'd lowered himself even more! It was so hard to resist the urges when every glance at his body made him aroused. Every twitch of his glutes or itch of his new hair was like a scene from his deepest fantasies. And in each one, Geoff the human ended up a common ass as he came, powerfully aroused from the delusion. But he'd never wanted it in real life, had he?

Geoff slowly came to the conclusion that he had to get some help. He couldn't fight this by himself. He had to get to a hospital or a clinic, somewhere he could be sedated so that he would not change any further. He could not afford to cum again! Soon there would be no more of the human Geoff left!

Yet, he had so trouble focusing as he searched the room frantically for his keys and his wallet. Those things seemed so human so far away. The stench of sex and the new hormones flooding his body were more than enough to keep him distracted. It was so hard to think, to focus on anything other than his sexy bestial body.

In a few moments, he completely forgot what he had been looking for. He needed to get out but...how? With what? How did humans travel long distances on two legs, without the support of four firm hooves on the ground?

Confused, Geoff sat down hard on his couch, trying to take a moment to reflect on what it was he needed to do. He was clad only in his underwear at this point. That was it! Clothing! Humans wore clothes to protect themselves from the elements. But why? Did he really need something like that to cover him when he had such lovely fur?

Despite the conflicting thoughts, Geoff was able to get himself up and make his way to his bedroom once more. He strode in, careful of tipping over from his top-heavy body as he pulled a pair of pants off the floor with his stiff fingers. A cautious sniff reported they reeked of humanity, and while Geoff found the scent off-putting, part of him knew that he needed to wear them.

Lifting the pants, he tried to squeeze one heavy hoofed foot into them, almost losing his balance and falling onto the bed in the attempt. They felt uncomfortable as he pulled on the pant leg, wondering why humans bothered with such things. The fabric made his growing swashes of fur prickle as he steadily worked in his other hoof-foot. Still, Geoff tugged on the constraining pants, feeling them become very snug as they were brought closer and closer to his massive hips. He grunted a little as he felt them touch his bare black balls, the sensation making him shiver.

The conflicting sensations made him pause, however. He wanted so desperately to touch his warm plump orbs, his body awash from the sensation of them filling once more from his bestial changes. Not able to focus on anything else, he fell back on the bed as his massive hand rubbed the contours of his hairy testicles, loving their girth and texture. His exploratory fingers felt every inch, every vein, bump, and ridge as his other hand trailed its way up towards his distended stomach.

His cock tip was just barely poking out of the tip of his large fuzzy donkey sheath now, and thin trails of pre-cum were spreading over his already-expansive chest. Everywhere the leaking precum touched, his skin grew more coarse with fine gray hairs following, sprouting up to form the next section of his pelt. It was a catalyst for the changes, leaving him bare of human skin for more welcome donkey hide.

Yet Geoff hardly noticed the changes, enraptured by the small tremors of pleasure from even the briefest of touches that were enough to keep him gripping his massive weighty balls. He moved his stiff fingers lower, down towards his taint, and closer to his puckered equine ass. He rubbed his chest, spreading the precum over his equine hide as his cock began to bob up and down in his sheath. Getting close once more, he felt the tension building in his balls, the release that would make him bray once more...

A sudden sharp fear broke him from his nearly orgasmic reverie. Geoff stopped himself, ashamed that even the briefest of touches, the smallest trickles of pre leaking from his massive cock were enough to rob bits and pieces of his humanity. He couldn't believe how much the thickening hide had spread just from the simple touch of his thick precum. Even his stomach had looked a little more distended, the veins stretching wider to make room for the asinine form he was soon to possess.

Deep down, Geoff knew he had to stop touching himself, that even without orgasmic release the changes were slowly invading his human body. He knew it was wrong, that he needed to get out of here and do something to prevent the process from going any further. If he did nothing, he would...what?

Yet, whatever magic changing him was steadily invading every aspect of his being. It was so rewarding to feel such pleasure for exploring his changed flesh. He couldn't help but want to rub at the silly bits of human flesh still clinging to his form, to experience the blissful sensations rolling off of him and out through his crotch.

Lost in lust once more, he let his pants fall uselessly to the floor as he awkwardly waddled, as if in a haze, towards the outside. The more he tried to think of what he needed to do, the more the siren song pervaded his thoughts. Shouldn't he just touch himself and let the pleasurable feelings flow over him? It had felt so good...

'No!' A swelling of human resistance surged in his mind. He couldn't let himself give in, no matter how good it felt. He couldn't let this 'magic' control him. That was it! The magic couldn't affect him if it wasn't in his system anymore, could it? And his swollen balls had to be the source! If he could just empty them, then there would be nothing left in his body to change him, and he would be able to think of a plan.

Geoff knew he had to be quick. His balls filled so quickly now, it was almost impossible to imagine properly emptying them. But the idea of this manner of salvation was so firmly implanted in his mind, he stubbornly took his thicker fingers and began playing over the swollen balls, messaging them as his other hand reached down to stroke his cock. He firmly believed that if he was fast enough he could expel the magic causing his changes.

Geoff felt so proud of himself as he began humping his growing shaft, rutting into his stiffening fingers as he braced himself against the wall. The aches in his spine and hips intensified as he stroked himself off, forcing him to lean further back against the wall from how hard it was for him to stand. But instead of being scared of his changes, his transformed mind simply attributed the changes in his stance to the magic's hold over him. It knew what he was doing and was trying to stop him! He cursed the magic with a thunderous bray as he stroked faster. He wouldn't let the magic win!

Fingers were stiffening now as the precum from his cock began fusing them together, the hardening surfaces making stroking himself off more and more difficult. Yet no matter how sticky and firm his hands were becoming, Geoff would not let the magic win. He switched hands, taking one developing hoof off his cock as he moved his still dexterous hand from his balls. His donkey dick was so girthy, he couldn't even get his fingers around it. But still, he managed to stroke enough to let the pressure build.

Despite the lack of direct stimulation to his testicles, it still felt like invisible hands were stroking his balls, making the pleasure radiate outwards towards his throbbing donkey meat. It was like a hand was pushing down on his back, bringing him closer and closer to all fours. One was teasing the rim of his equine pucker, and yet another was stroking his leaking cock in tandem with his barely human hand.

Geoff's mind started to cloud as the phantom fingers began to play over his still mostly human head. He could feel able tingles of fingertips playing over his ears, bringing them up to a proper donkey's length while coating them in lovely gray hairs. The fingers played down his neck, adorning him with a black mohawk that burned down over his crunching shoulders. They entered his nostrils and tugged, pulling them outwards along with his growing muzzle. He could even feel the fingers pulling at his teeth, making them into thick slabs as his muzzle stretched out to its full length.

Next, the fingers pressed on his forehead, causing it to slope and diminish the space in his mind for human thoughts. Confused, Geoff began to instinctively lower himself to all fours. He quickly forgot why he had been fighting. It was what his body had wanted, after all, wasn't it? All of his thoughts began leaking from his cock as useless seed, leaving only the instincts required to feel pleasure at his growing form. His hand slipped, almost a hoof itself as his cock slapped up and down over his sheath and stomach.

Too late, Geoff realized that he should not fall onto all fours. That was what he had been fighting against all this time, wasn't it? Yet his changing mind could not remember why. Being on all fours felt more comfortable, after all. Part of Geoff's instincts struggled to stay on his hind hooves but he was slowly losing centimeter after centimeter as his body was lowered to the floor.

Though he could no longer rub it, his cock slapping against his stomach and the sensation of phantom fingers were enough to bring him to the edge of the waterfall. One final human thought burbled to the surface, knowing that if he did fall to all fours, he would be doomed, that there was no going back from an asinine existence. Yet it was already too late. He could not stop his body from falling to its eventual fate. And, more to the point, he no longer wanted to. That last human thought blew forth from his mind, dissolving into the sea of seed that was swelling within his mighty asinine testicles.

"HHHEEEEEEHHHAAAAAWWWWW!" He cried with a mighty bray, showing to the world what he really was at last.

The new donkey fell to the floor with a heavy clomp, the vibrations rolling through his musky body enough to push him over the edge into a final orgasmic release. His cock bobbed up and down as he coated the floor with his slick donkey cum, truly the seed of a jackass now. His massive equine body shivered from the release, feeling content and happy that he'd successfully orgasmed.

The newly-birthed donkey kicked and bucked from the feelings of orgasm as he shed the last remaining torn garments stuck to his frame. His stomach rumbled fiercely, though he could not scent any food in the nearby area. Slowly, he made his way to the front door, a dim memory of what it was and where it led in his mind as he pushed against it with all his might. The scents and sounds of the world beyond swept any lingering humanity away as the new donkey made his way out into the warm day and the grassy yard full of food to sate his new appetite.