Looking out into the empty zoo, Rowan found himself wondering, not for the first time, if he wasn’t insane by agreeing to come out here at night. Surely, the ad he’d found was legit, given it was posted on a public forum. Rowan was likely just being silly in thinking there was something nefarious afoot. Still, save for a few zoo employees, and of course, the animals, it was likely he was largely alone here. That in mind, Rowan had to admit it was hard to completely eliminate the nervousness. 

Not that what he was here to do wasn’t worth the risk. The volunteer experiment he was here to participate in promised to pay 1000 dollars up front, something that would keep him in his apartment for another month. Having graduated with his master’s a few months ago, a lack of employment in his city, as well as the looming threat of student loans and bills, left Rowan in desperate need of some quick cash. Unfortunately, there was little information about the particulars of this experiment, though he was told he would find out once he got there. So what if it was to take place after closing hours? It was well worth the risk, and surely a local zoo wouldn’t do anything to harm him, right?

“Ah, Rowan? Sorry about that, I had some extra paperwork to finish. I hope I didn’t keep you waiting for too long!” A man exclaimed, coming out and shaking his hand. Introducing himself as Devon, Rowan smiled nervously, returning the gesture before replying, “I’m ready to get started! Looking forward to it!”

With his shyness, Rowan was remiss for not asking what the experiment entailed right away. Still, he eagerly followed the man, trying to repress his previous concern. “Sorry to have you here so late, but it couldn’t be helped. This type of interaction works best if the guests aren’t around. It might influence the animal’s behavior in ways that could cause outliers. I’m sure you’re familiar with such methods, given your academic background,” Devon explained, and Rowan nodded enthusiastically. In truth, he was always a bit of a night owl and didn’t mind being here after hours. There was a novelty to the experience he found rather exciting, being in a zoo this late at night. 

Following his guide, Rowan found himself looking from one exhibit to pen, trying to get familiar with the exhibits. There were plenty of animals preparing for their nightly activities, everything from monkeys to big cats to birds in their cages. It really was a different world at night, even if the trails were illuminated with bright lights. He wanted to ask Devon where they were going, but thought better of it in the end. He was excited to do whatever they required of him, hoping to get into their good graces by being a successful participant. Not that he had any idea if they needed further research participants, and didn’t want to be too forward on the matter. But if there was an inroad to a more permanent position, Rowan was willing to do whatever it took!

Eventually, the man led him into a small building, one situated at the rear of one of the enclosures. Figuring it was employee access only, Rowan followed eagerly, wondering if he was going to see some of the animals up close. Being led through a back room, the man soon opened a gate to the pen beyond. Encouraging him to head inside, Rowan hesitated a little, not sure it was safe. “Go ahead, it’s empty,” Devon assured him, and Rowan did so, looking around the large habitat. There was a wide area of grass with a large trough in the middle, and a few scattered giant rubber balls that were likely toys for whatever animal was supposed to live there. Rather spacious, all things considered, likely for a larger species. 

As Rowan looked around, a strange smell soon flooded his nose, one that he found rank and pungent, like something from an animal’s backside. Rowan’s eyes gazed rapidly back and forth, figuring the cage’s occupants were indeed present and had maybe relieved themselves. Yet, the sight of Devon donning a gas mask set a shiver down his spine. He couldn’t see the man’s expression, though such made Rowan further concerned. Devon simply pushed the gate closed, backing away and standing like a statue, though waiting for something to happen. 

The horrid smell burned into his nose, making Rowan want to vomit. It reeked of flatulence, likely from some kind of animal. He wanted to call out, though the scent seemed to seep into his nose and mouth, making him gag. It was soon overwhelming, and Rowan fell over, landing on his knees and coughing violently, desperate to get away from the rank stench. Yet, it seemed to swirl around him, settling into his very skin. 

“Ahhhh, it stinks!” Rowan managed to cry out, though it was only when the gas had dissipated and he wasn’t breathing it in directly. He managed to stand, mind fuzzy and stance wobbly. The stench of flatulence still clung cloyingly to him, something that he figured a hundred shows wouldn’t remove. But he managed to keep his wits about him enough to stumble to the gate, trying to pull it open to no avail.

To his shock, Devon was still standing there, only now pulling off his mask and regarding the man with a sinister grin. “Everything will be OK. It’s all part of the trials, and your data will be invaluable to the zoo’s operations. Just let it happen, that will be easiest,” he said simply, even as Rowan continued to bang on the door, feeling helpless as he did so. 

No matter how much time passed, the stink in his nose would not abate. In fact, it seemed to grow worse, if such was possible, as though he was still being subjected to the gas. Yet, it was soon forgotten with a series of strange sensations coursing through his body. Against his understanding, Rowan started to feel somewhat bloated, as though he’d eaten a big meal. It was enough to force him to belch, and the rank taste of the gas was on his breath, making him want to vomit once more. Yet, there was little he could do as the discomfort in his body rose, as though his own gases were building toward the breaking point. 

A surprising tingling sensation on his backside made him groan, as though his tailbone was being strained. Reaching back to touch it, a strange bump met his fingers, one that was gradually starting to expand as he played with it. More confused than afraid, the lump soon pushed out against his pants, straining his underwear before Rowan saw it fit to pull it out. Pops of growing bone and muscle soon extended it far longer than anything he could imagine on his body. A cold shiver ran through him as the thing started to twitch of its own accord. As the skin turned coarse and the tickling of what had to be hair poked its way out of the tip, Rowan couldn’t help but equate the protrusion to be some sort of bestial tail. Yet, how the hell could something like that push its way out above his ass?

The tingling seemed to grow worse as it settled into the muscle and fat of his ass cheeks. Rowan was unable to stifle a grown as his anus began to tickle unpleasently. He couldn’t be sure what was happening without touching it, but it seemed the skin was parting around his hole, as though allowing further room to grow. It was happening so gradually that Rowan couldn’t help but reach back to touch it against his better inclinations. To his shock, a seeking finger was accidentally inserted, making him groan from the stimulation. The puckered anus he now posseed was almost pushing its way to sit under his newly-grown tail. And with the meat of his ass cheeks parting, he could almost feel his hole touching the fabric of his underwear, a powerfully uncomfortable sensation he could not escape from. 

Yet, Rowan hardly had time to focus on the discomfort before his belly began to bloat at an uncomfortable pace. The force of it soon pushed against his shirt and causing it to rise slightly. Rubbing his belly only served to lightly alleviate the ache as it soon grew well beyond what his frame was meant to contain. There was fat there, to be sure, Rowan feeling pounds and pounds being added in mere moments. But his paunch was rather firm as well, as though muscle persisted underneath. It was of little consolation as his stomach continued to distend, pulling his shirt upward toward his pecs. It was impossibly tight against his frame, though Rowan was largely unconcerned with the rest of the changes coming over him. Surely, it would be impossible to remove without tearing it, though Rowan was more fixated on his belly, rubbing it frantically and trying to steam the changes, likely in vain. 

The changes were clearly more than surface level, a consistent gurgling in his guts making him groan. It soon descended down his throat, and Rowan was embarrassed as gas seemed to build and force him to let out a hearty belch. Embarrassed, Rowan had no ability to stop, moaning between belches as his guts continued to pain him. Perhaps worse was the gas descending toward his meaty, wide-open pucker. Rowan felt shame bombarding him as he let out a loud series of farts, followed by a pungent stench that made him want to retch. It didn’t escape his notice that the stench was almost identical to the gas he’d been hit with previously. Without an understanding of what was going on, Rowan was left to suffer. 

The effect of his flatulence seemed to swell his ass little by little, leaving his pants to tighten almost painfully against it. As best as he could tell, the skin was firming up, tighter than what the waistband could dig into. Still, the growth served to raise his panic, eyes darting around the enclosure as he looked for an escape. Yet, it was obvious he was as trapped as an animal in the zoo, and even if there was an exit, the pain in his expanding guts made running out of the question. Farting more relieved the tension slightly, though the stink of it hardly made it worth it. What the hell was happening to him?! He reeked like a zoo animal!

A further surge of growth pulled his shirt over his pecs, which were starting to barrel and stretched the fabric taut. As much as Rowan wanted to pull it over his head, the sight of his altered skin gave him pause. It was turning ashen, darkening, and thickening toward a leathery texture. Swelling of the skin around his legs and upper arms gave him the idea of partitions, almost reminiscent of armor. As curious as he was to touch the skin, part of him feared it might spread to his hands. All Rowan could do was moan his discomfort, muddied by a series of rancid burps. He couldn’t imagine what was happening to him. The armor-like skin was steadily spreading, moving down his legs and arms. It had even started to crawl up his neck, removing any errant hairs along the way. 

Trying to call for help came out as a heavy burp, once more making him feel queasy. The sickness in his guts caused him to keel over, putting pressure on his ass and causing it to burst from his pants with a series of loud rips. His underwear remained for a moment, tightly encroaching on his thick pucker as he farted once more. The stench burned into his nose, something he was almost able to taste in the air as he stumbled forward. His exposed skin gave off a sweaty, animalistic stench as well, and Rowan couldn’t help but cough, unable to get the stink out of his nose. 

Yet, the more he drew in his heady bestial redolence, the more tolerant Rowan became of the pungent bouquet. In fact, he could feel his nose reflexively sniffing, trying to draw it in as though his being depended on it. It took him a few moments to realize what was happening as a hand reached down to tease his groin through the fabric of his underwear. It felt amazing, Rowan groaning through a series of rank belches. There was nothing he knew of to cause him such arousal, yet no denying his lust as widening nostrils drew in the scent. His skin was damp from the sweat of exertion, though he was almost giddy to feel his rumbling bowels expelling gas as his nostrils flared further. Even over the bestial stink, Rowan could smell his leaking pre-cum, and it was enough to make him touch himself, consequences be damned!

In his desperation to get off, Rowan was slow to realize his body had continued to bulk up all the while. By now, his shirt had torn down the back, and the fragments slid off his ashen hide. The meat and muscle swelling under the skin was almost painful, and efforts to rub it made him grunt his frustrations. It seemed his skeleton was gradually altering as well, and with it, restricting his ability to flex. It was almost maddening with his need to cum that his arms could hardly move sideways. Desperately, Rowan worked to contort his body in ways it was no longer meant to move. As heavy cracks and pops forced his humanity to expand, Rowan could only grunt his lament, voice somewhat stunted and garbled by his persistent belching. 

As much as it had been extending all the while, Rowan was still a little surprised to feel his tail rise reflexively. Almost immediately, his anus began clenching to release another pungent bout of flatulence. Yet, as his nose drew in the bestial stink, Roawn had a harder him recalling why such had bothered him earlier. Not just the smell, that was something he was steadily growing accustomed to. Rather, the fact that he was gassy required immediate relief, and raising his tail to do so was as natural as for any animal. Animals did what they did, after all. What was he so concerned about?

No sooner than the latest wave of stench hit his nose than his cock lanced forward, doing away with the remnants of his underwear. It was rapidly outgrowing its human contours, swelling against the skin and adding a few additional inches. As Rowan focused on its length, he realized he could make it twitch somewhat, flaring the head as it continued to engorge. As best he could feel, his former foreskin was being outgrown, the base swelling large enough to pull it back against his hairless groin. As much as his rod was reconfiguring to an animal’s member, his testicles were soon to swell to supply its needed sperm. Rowan couldn’t help but groan as they expanded, almost heavy on his groin and needing to be expelled. 

While he could still look down, the sight of its animalistic girth was shocking, had he not been so needy. But in his current state, Rowan couldn’t help but delight in the changes, eager to see its bestial shape and feel the pleasures it might provide. It looked like nothing he had ever seen, making Rowan desperate to touch it as it reached his straining arms. The head and base were both thicker than the shaft, leaving his penis to undulate its need as he focused on it. Its shade lightened toward pink, though grey splotches peppered its girth. Yet, it was the head that truly alarmed him, pulling almost concave as its edges blossomed out into five individual points, more akin to a starfish than anything. This was the head of his penis now?! And yet, its shape did little to deter his desire to touch it…

Grunting, Rowan’s struggling arms finally managed to caress the edges, sending a shiver of pleasure through his entire being. It was almost enough to white out from even that brief contact, and Rowan continued to touch himself eagerly, piss head already leaking. Eventually, his bobbing length came close enough that he could grip it properly, and Rowan did so, reveling in the sensitivity of the shaft. He rubbed at it frantically, not only for pleasure but for a concern that he couldn’t quite eliminate. After all, with the steady onset of changes, he was sure to lose the ability to touch it soon. It would be the ultimate humiliation to bring himself so close only to lose the ability with his altered anatomy. 

Thankfully, his efforts were enough to leave it slapping against his belly. Rowan felt his entire girth being stimulated all at once as he rubbed the head frantically. His massive testicles swelled underneath him, tensing as his end drew near. A surge of growth overcame them, followed by a discomforting pop as though they were being pushed upward. It seemed they had become enveloped by his insides as the pressure grew to the point of no return. And with that, his eyes fluttered shut, the blood and energy required for such an act almost too much. It left him unable to do more than to bask in the end result…

The twitching within his pulsating cock was enough to pull it from his grip, though not before Rowan was hit in the arms and chest with a few blasts of rank, yellowish cum. The force of it caused him to tip over, though his firm skin felt little of the impact as he laid there, cock still slapping against his belly and extending his orgasm. Bestial whines escaped his lips as his orgasm carried on, longer than he could imagine. Yet, there was no denying how natural, how right it had been to cum from such a cock. If it felt this good, smelled this amazing to be turning into an animal, why had Rowan looked to leave the pen in the first place?

A tingling in his hands drew him back to the present, and Rowan raised them with curiosity as the nails started to swell. They were quick to encompass the surface, taking much of the fingertip within. Three fingers persisted while the others remaining were steadily being pulled within his wrists, along with his thumbs. All he could do was try to twitch them in vain as the joints and muscles within popped apart and dissolved into nothing. He could barely perceive the bones within reconfiguring, leaving little of his palms as his wrists continued to stretch. It was his former fingers that had most of his attention, the keratin swelling into thick slabs that took up most of the space of the former digits. They were massive. Rowan was only able to bend them from the wrists as their girth expanded and they began to weigh heavily on his arms. With the way his shoulders were being forced forward and his chest barreled, Rowan was sure he would be able to support them comfortably, rather eager to see how they might complete. 

As much as Rowan knew he should have panicked, a strange sense of calm fell over him, as though the changes were natural and desirable. After all, with his massive bulk, he would surely need such large hooves to hold him up, right? And then there was his cock, Rowan delighting in feeling it retract back into a leathery sheath. It was powerfully pleasant, Rowan still able to feel it bobbing a little as it settled within him. His body was growing, straining all the while, and Rowan was left to adjust his stance, moving his arms and new front feet to better take his weight. 

As much as it felt right to be down on all fours, further changes were required to leave him there. Rowan welcomed them, feeling a brief ache from within as his pelvis shifted, hips pushing outward and flattened into his bulging stomach. His legs had much further to grow, the meat and muscle expanding within to allow proper support for his stance. In sequence, his thick chest forced his shoulders forward, and hunching his arms forward, Rowan finally found his posture manageable. He would be down on all fours forever, but it was harder and harder for him to find fault with that. It felt natural, his body gurgling as it continued to solidify into an animal form. One that cared little for modesty, much less bills, jobs, student loans, and all the other things that had plagued Rowan’s mind for all these years. 

As though his relaxation was enough to trigger an innate reaction, Rowan could feel his penis coming out of its sheath once more as the fullness in his enlarged bladder made itself known. He had no control over the action as his penis unfurled of its own accord, nearly touching the ground before his bladder let loose. Not expecting it, Rowan was a little taken back by the force of piss being excreted, splattering on the ground as his cock swayed back and forth like a hose. The stench of piss was rank and strong, but to Rowan’s changed senses, it hardly seemed to bother him. It reeked of his essence, and even the feeling of it splashing on his hide didn’t bother him. It was a natural act, and even though the smell clung to his nostrils, it was quickly forgotten. Rowan was rather focused on trying to move in his new body as he walked away from his piss.

Still, there was no ignoring the sensations of change remaking his humanity even as he struggled to become more comfortable in his growing frame. In particular, the pressure in his guts was still increasing, especially as his internal organs shifted and forced his still-digesting food through his system. Once more, his tail lifted in reflex to the churning in his guts, only this time his sphincter was inclined to relax as well. With surprising force, Rowan felt his body eject a rather large pile of rhino dung, gathering behind him as his bowels let go without his ability to control himself. He was barely aware of what he was doing until the rank smell of shit hit his nose, almost enough to make him ill. Yet, the relief it provided was more than worth it, and a fading part of his mind found it fit the question why he hadn’t always moved to relieve his bowels whenever necessary. It was far more efficient, in his opinion!

The stench of his waste, too, was forgotten as the pressure in his shoes grew beyond what he was able to take. Like his fingers before them, Rowan found he had no ability to twitch them any longer. Yet, it was harder for him to mourn their loss as the skin separating the digits merged together and forced two toes within his foot to be repurposed. Their growth was rapid enough for him to feel them burst from the back of his shoes, and he tried his best with limited flexibility to kick them away. It mattered little as the toenails rapidly expanded, sitting at the ends of his former toes as spongy flesh made up their circumference. Like his former hands, the column-sized legs were situated to leave him walking on tiptoes, a bizarre sensation, though hardly the strangest thing to come from the change. As leather burst and socks tore off, Rowan walked forward with more success, ignoring his piles of waste under massive three-toed hooves barely able to feel beneath them. 

While he had grown significantly over the past ten minutes or so, Rowan could feel an increase in weight coming faster, given he now possessed the bone structure to better support it. He would be several thousand pounds by the time the change was done, and it was becoming harder for his foggy mind to find fault with that. His skin was gray and firm all over, save for his head, which looked comically smaller compared with the rest of him. Even his neck was thickening now, his jaw cracking and bulging up with mass as the gray skin started to encroach over his chin and neck. Organs were massive, finally settling within him as his tail raised to fart once more, barely noticed under the steach of his waste. Yet, Rowan could only find comfort with his new form, growing into a beast that was steadily feeling more and more like his true self. 

The scent of something else pungent and heady soon caught his attention, and Rowan looked over to the sound of a gate opening. He couldn’t see as well in the dark, and his eyesight seemed rather poor besides. But the scent was too much akin to his own that Rowan couldn’t help but feel his elation rise. Best of all, the animalistic odor served to make him horny, imagining a massive musky male rhino the same as he was becoming. And as a gargantuan form trotted toward him, Rowan was sure he was to be granted his wish. 

Rowan was barely aware of his ears now twitching at the top of his larger head, natural as much as the ones the animal before him possessed. There was something almost familiar about the beast, though Rowan’s musk-drunk mind could hardly be brought to place it. He could scarcely understand where such a magnificent specimen had come from, but there was no denying how Rowan felt about the company. And how much his body responded to it, cock twitching under him and eager to be used. If only this other beast felt the same way! 

Not sure what to expect, Rowan felt his body still, hearing the beast trotting rather quickly behind him. Rowan felt his tail rise reflectively, and the moment it did so, the massive beast moved to goose his pucker. A small part of him worried about how dirty he was back there, though it did little to deter the other rhino’s efforts. Soon, his heavy breath was on Rowan’s anus, the beast breathing in his stink with all the insistent of an animal. Without really thinking about what he was doing, Rowan felt his stance stiffen up, as though waiting for something. All the while, his penis was writhing against his belly, needing to get off as his body shook from anticipation. The beast was so close, and there was no denying the stench of his arousal, even to Rowan’s unchanged senses. All he had to do was wait!

Soon, the rhino was finished and had moved in front of Rowan so that he might reciprocate. With his ass so close to Rowan’s nose, the former man was a little disgusted, especially given the odors rolling from the beast’s behind. But to his changing senses, more nuance persisted under the stink that Rowan couldn’t help but take a deep breath, committing it to memory. As he did so, Rowan felt his nose stretching, running it from the animal’s asshole down toward his tail and balls. Firming his stance, it seemed the other rhino was just as insistent, leading Rowan to believe that raising their tails for each other and sniffing was more of a greeting to their new species. And it was certainly becoming something Rowan could understand!

As he did so, a gurgling in the rhino’s hind end drew the attention of Rowan’s ears before he let loose with a bout of noxious gas. The stench of flatulence was immediately familiar, not simply from his own bowels. It was the same stench as the dose he had been given before being left in here to change. Now, Rowan couldn’t help but think he was getting it from the source. As disgusting as it should have been for him, it was the most alluring scent he had detected, and Rowan leaned into it, hoping for more. Any fading concerns were erased as his mind became enveloped in stinky miasma, and Rowan felt his mind shut down, enjoying it fully.

Lost in his musk-drunk mind, Rowan was largely ignorant of the changes that began to accelerate over his body. A tingling began to play over his face as it began to push forward with a series of wet cracks. An already thicker neck gave way to a massive jaw, pressing against the rhino’s rear as the beast huffed his eagerness. A larger, curious tongue started to rim the beast’s ponderous pucker, not caring about the taste as the other rhino seemed to get into it. The scent of pre-cum leaking from the animal’s cock was all Rowan needed to keep up his oral ministrations, running his tongue around the rim and even inserting it into the beast’s asshole directly. He loved the animal’s backside, and as his thoughts continued to erode, the notion of this creature as a mate became stronger to the point Rowan couldn’t recall anything but.

As the other rhino backed into his rimming, Rowan found it harder and harder to focus on his waning humanity. While most of his body already matched the beauty of the beast’s, there was still some room to grow. Rather than be concerned with the loss, Rowan’s waning mind wanted nothing more than to be like him. Both were painfully erect, Rowan desiring to bring the beast pleasure. His tongue worked in and out, prompting the other rhino to dose him once more and bring forth the changes he desired.

As his hair fell away and his muzzle cracked forward, Rowan felt his compulsions reaching their breaking point. With surprising skill, he was able to back up and get up on the beast’s behind, grunting all the while. His leaking cock tip rubbed frantically over the rhino’s balls and taint before finding a hole, one puckered and protruding enough that he was able to push in with little resistance. He was a little too small to insert himself in all the way, though with a surge of growth, Rowan found his stature expanding with enough force that such was little concern. Without even needing to thrust any longer, Rowan’s penis was pushed into the hilt, resting there for a moment before bestial lust took over. 

Thrusting faster than any human could manage, Rowan was barely aware of the final changes to his form that made him into a beast to match his lover’s. His head was massive, eyes smaller and squinting as he struggled to take in the contours of his mate’s backside. It was his widened nostrils that truly told him all he needed to know, however. This rhino was like him, a mate, a companion. They belonged together as much as their combined musk confirmed that reality. A wider tongue and thicker teeth were welcome, far removed from what he once possessed, though desirable with the overall outcome. An elongated brow stenchced further in front of him, and the more Rowan fucked, the larger and heavier it seemed to become. It simply felt right in a way that brought peace to his addled mind, and Rowan pumped his penis in and out with vigor. Their bodies rocked as Rowan’s changes came to a conclusion, and with it, the death knell of his humanity and all he had been before this moment of pleasure. 

The impending orgasm almost whited out Rowan’s mind from awareness of his final changes. As far as his nose was away from his eyes, he could still perceive the outline of something thick pushing its way through the skin above his lip and nostrils. Firm and formed of tightly wound hairs, Rowan relished its growth as his penis pounded his mate toward their mutual conclusion. As best he could tell, his mate possessed one, so it was certainly appropriate that he develop his own. It was hardly an inconvenience to his face as it grew above his snout, thickening out from the base. Though as much as Rowan wished to focus on it, the tension in his testicles was too much, and he fell into a needed release. As his semen pumped into the other rhino’s rectum, Rowan felt his mind whiting out, instincts at the forefront as a second horn grew behind the first, barely recognized in the orgasmic explosion to come. 

Bellowing out, the beast that had once been Rowan dismounted, a pleasant fog enveloping his mind in a post-orgasmic lust. While there was a thread of recollection that he had been something other than human, it mattered little. Rowan was content to move toward a bale of hay nearby to feed now that his lust was satisfied. Still, a thought was spared for the rhino’s back end, where his semen still leaked out from the beast’s abused pucker. The new rhino moved to sniff at it, even giving a lick to cement their new bond. There was something of the former human there, a spark that lit up with the thought of having a companion, a mate. Yet, even that lingering thread was erased the moment his tail raised and his bowels deposited another load of rhino dung, taking a sniff of the other one without a human thought left remaining.

Bowels relieved, the new rhino moved to nuzzle his mate, oblivious to any past that didn’t involve the other rhino or the pen where they lived. This male was a source of comfort to him, the scent of his hide and semen sign of his purpose and their companionship. The two had no need for words as they moved over to a hale bale in unison, sniffing and huffing with their massive bodies. Rather pliable lips reached out to grip their grassy meals, and the two of them stood there until morning eating their fill and flicking flies away from their exposed anuses with ropey tails. Often, the new rhino raised his tail to fart, though he cared little of it, the act natural to his new animal body. Only a regular twinge of arousal reminded him of something he had forgotten in the past. Yet, the rhino cared little beyond that, dimly anticipating when his cock would reach erection and he would mount his mate once more…

******

Devon couldn’t help but grin as he watched his new rhino get along well with his mate. It seemed he had chosen well, as quickly as the former man had taken to his new body. It mattered little, given there was likely nothing of his humanity remaining in the beast. Still, it boded well for their new bodies and beings when his subjects accepted their new bodies during the process. It was quite permanent and one way, after all, with no sign that the subjects were anything but the animals they now were. 

His experiments were still in their early stages, of course, hence the lack of need to convert a subject to a female. It seemed the inclinations of those changes were geared more toward same-sex pairings, regardless, but it mattered little when insemination could be performed in vitro. It was a slow, ineffective process in preserving a species in the short term. Even Devon had to admit that. But the combination of human and animal DNA would always result in a unique genotype that would add essential genetic diversity to wild populations, one day. And that day was coming sooner than he hoped. In his estimation, he only needed to test his formulas on zoo creations a few more times before the process was ready to be introduced on a much larger scale…