“That’s it boys nice and slo-“ Jenkins was cut-off abruptly as two strong pairs of arms grabbed him. “What the fuck are you doing? Get your hands off me.”
“Sorry doc” one attendant replied “we know what you did. Just how long have you been plotting to take over our stables?”
“Yeah” another added “you’re just a jumped-up little nerd. Think you’re so smart don’t you? You thought getting rid of our boss would solve all your problems didn’t you!? Well I’m afraid your problems are only just beginning.”
“No you idiots” Jenkins said in an increasingly panicked voice “it was an accident. She injected herself by mistake.”
“Sure she did” the first attendant replied “how awfully convenient for you. Why didn’t you tell us instead of simply assuming command hmmm?”
“I-I’m sorry ok, just let me go and we’ll discuss it” Jenkins pleaded.
“Sorry doc we’ve discussed it enough already. We know just what to do with you.” With that, Jenkins felt a sudden jab of pain in his arm. He cried out as he saw that he’d been injected with another horse serum. Jenkins was given no respite as he was shoved inside Princess’ stall along with the new stallion. The attendants exited the stall and locked the door from the outside. However to Jenkins’ dismay they didn’t leave, instead they huddled round to peer in, obviously expecting something exciting to happen.
While Jenkins tried to take stock of the situation the other two horses in the stall were getting to know each other. Both of them were clearly incredibly horny and were itching to satisfy their primal urges. Princess had her backside on full display to her soon-to-be mate. Her tail was raised and her vagina winked as it moistened with arousal. Her feminine scent mixed with the stallion’s musk in the air. The new stallion was incredibly receptive to the mare’s invitation. His penis was now fully erect and dripping precum, readying itself for some action. Before long he was burying his muzzle beneath Princess’ tail, savouring her intoxicating aroma.
In the meantime, Jenkins felt sick. He could feel the first symptoms of his serum starting to take hold. The bud of his new tail pressed against his trousers while his digits ached as they began to fuse together. The distraught man looked up to see the attendants laughing and jeering at him. “Please stop this! There must be something you can do?!” The only reply was that of louder laughter from the attendants. “Pl-Pleighhhh- Please!” Jenkins’ composure disintegrated as he began to sob as he continued begging. “I don’t want to be a horse. Just k-kill Meeeeeighhhhh!”
“Sorry doc we never abuse the animals” one attendant joked. “Yeah just RIDE it out” another jived. Jenkins despaired as he reflected on the hopelessness of his situation.
While Jenkins tried to fight his changes the two horses decided to get down to business. Prince withdrew his muzzle, which was now coated in the mare’s juices, before he lined himself up. Princess offered assistance by spreading her legs and hiking up her tail, hoping to draw him in to her soppy folds.
Princess whinnied lustfully as the eager stallion landed on her back. He was immensely heavy but she was able to cope. She steadied herself while Prince began eagerly poking with his cock. It took a few wide misses before he hit the mark. Both horses neighed in pleasure as Prince’s cockhead found the target. He then began shuffling closer to his mare, causing his rock-hard member to sink deeper into Princess’ eager loins.
As this was going on Jenkins continued to change. His midsection and backside had grown considerably in size and weight. Additionally his legs had become fully equine by now, all of which finished in fully-formed hooves. His balance had gradually been thrown off until he reached the tipping point. He cried out with a mixed human and equine noise as his front hooved clopped to the floor. There was then an agonising popping sound as his hips readjusted themselves for four-legged travel.
Unbeknownst to Jenkins there was one major change yet to take place. He felt strange as a tingly sensation struck his manhood. He wasn’t able to see what the commotion was but he certainly felt it. His eyes widened as his junk moved up towards his tail. He winced as the flesh began to shift uncomfortably. He trembled as his scrotum grew taught and reformed into a distinctly female pair of lips. As these lips puffed out and gained a leathery texture his shaft withdrew between them, leaving only the nub of an equine clitoris in its place. As Jenkins’ new orifice opened a new channel developed deep within him, leading to what would soon be his new womb.
“A mee—meighhhh- MARE?! Neighhh, no! Not a fucking mare! NEIGHHHHHH!” With that Jenkins’ human voice abandoned him. He continued to whinny in protest which drew more laughter from the crowd.
Jenkins looked around in dismay, hoping for just a shred of comfort. His eyes soon fixated on the two horses mating in the stall with him. By now Prince was eagerly thrusting inside his mate. His member slipped in and out of the slick folds with ease as he hilted his cock inside the mare beneath him. She was clearly enjoying herself as well. She moved her hips in time with his thrusts, all the while whinnying out of sheer lust. The result of their passionate lovemaking was easy to see as juices dripped down Princess’ hind legs and on to the hay beneath them.
Jenkins should have thought nothing of it since he’d seen horses mating dozens of times. However, Jenkins’ human mind was rapidly losing control. New instincts clouded his thoughts as female hormones flooded his mare’s body. He watched the shaft pumping in and out and he couldn’t help but feel… jealous!
The very notion was deeply disturbing to Jenkins’ human side. Unfortunately this half of his consciousness was being suppressed by his developing mare instincts. As a result of the serum his body was already going into estrus. He began to feel wet between his legs as the fire of his first heat started to burn.
This intensifying need accelerated the changes towards their conclusion. Jenkins continued to protest as the last few alterations took place. An elegant chestnut colour settled over his body while his neck and head grew to more equine proportions. His neck lengthened and thickened with muscle while his face pushed forward into an equine muzzle. The last few tweaks rounded off as a pair of nipples poked out between his legs and a white stripe formed on his face. After these changes finished Jenkins was gone. He, or more accurately she, was now a graceful chestnut mare.
The attendants cheered as Jenkins’ transformation ended in success. Clearly their loyalty to the former stablewoman knew no bounds.
“So what should we call her then?” The attendants pondered for a moment. There was an awkward pause as the not-particularly academic crowd struggled to think of a fitting name for the new mare.
“Urr… how about ‘Jenny!’ one attendant finally blurted out. “You know coz it sort of sounds like ‘Jenkins’ doesn’t it?” The others shrugged in indifference and so the name became official.
In any case, the new mare couldn’t care less about her stupid name. She was still mesmerized by the mating horses nearby. By now her own clit had started winking as her juices frothed out between her wet folds. Her own powerful scent began to mingle with the others in the stall as she used her new body to entice the sexy stallion.
Regrettably for Jenny, Prince was already fully occupied with his current mate. The way the mare’s vaginal walls clamped down around his cock sent shivers of pleasure running along its whole length. He knew he was close now. He was determined to complete his mission by impregnating the mare beneath him.
As for Princess, she was enjoying herself even more than the stud on her back. The feeling of the shaft as it rammed into her was heavenly. She felt immensely lucky and proud to have attracted such a handsome stud. The human side of her mind yelled out frantically for her to stop. But these pleas fell on deaf ears. She was determined not to mess it up now. She was desperate to have his foals!
The whinnies of both horses picked up in tempo and volume as they neared their long-awaited climax. Princess shoved her hips back over the long shaft, desperate for him to finish. She then trembled in relief as she felt the cock stiffen within her before firing its load deep inside her. Jet after jet of thick cum spurted out of the stallion’s massive tool. Mixed sexual fluids soon seeped out of Princess’ strained vagina as she was flooded with the sperm-rich jizz.
Jenny also shuddered as she saw their climax. Judging by the volume of cum that Prince had produced, his mate was almost certainly pregnant. She was so lucky!
Then, to add insult to injury, Jenny’s envy intensified further when Princess looked back at her with a smug expression. It wasn’t fair! She needed that cock as well! She wanted to be bred so badly!
As Prince slowly extracted himself from his mate the attendants continued to chuckle and point. Jenny’s arousal was clear to see. After a brief discussion they knew just what to do with her next…