He felt his asshole bloat a bit as it swelled into a donut shape. It also moved upwards to accommodate for his new mare pussy and pushed his ass cheeks aside in the process. His pants then thinned significantly and became skin tight leggings as his body hair vanished, being leaving behind only smooth skin and the hair on his head.
Jeff suddenly felt like he had to vomit as his organs shifted around in order to make enough room for his new mare pussy and womb. Not to mention his intestins adjusting for his new asshole as well. Finally, a pair of 3 inch long nipples grew on his lower torso on either side of his bellybutton. They then ballooned out into a pair of large human breasts, but actually functioned more like horse udders as they quickly began to fill with milk. To allow their presence, his hips widened out from his sides, leaving him much more room between his legs for his new breasts to hang down more comfortably, as well as allow his body to physically be large enough to be able to birth out a baby horse, if he ever were to become pregnant with one, that is. This ended the changes to his, now her body.
Jeff looked down at her body in a mixture of amazement and uneasiness. She hadn't fully expected it to work. And not as thourally either. She genuinely felt like she was a human shapped mare. Especially by the fact that her pussy was currently driving her insane. Only 2 thoughts came to her mind. The first one was realizing that she must be in heat, and the second was of a massive horse cock, the cure for her aching pussy. Oh god how she wanted that nice, fat, throbbing horse cock to fill her to the absolute brim with jizz.
Jeff stood up, and naturally stood on the tips of her toes as if they were hooves. Her torso was bent 90 degrees over at the waist and was impossible to straighten out completely, but due to he ass and hips now being significantly larger, she could still balance herself easily enough. So she just bent her back backwards and was able to at least look forwards as just the upper portion of her torso and her head were able to straighten out vertically. She walked to her full length mirror and was amazed by her reflection.
Looking back at her was a girl who looked to be the female equivalent of his prior appearance. However, her narrow waist joined a pair of hips that easily were 3 times their size, creating almost a 90 degree angle where they meet each other. She never even noticed her new horse tail either! She then began a cycle of looking at her reflection and then down at herself over and over again, just taking everything in. Her back was getting a bit stiff though, so she relaxed and lowered her torso forward, naturally placing both of her hands on the ground without thinking.
It took her a second to realize that it seemed a part of her had obtained the natural instincts and mentality of an actual mare too. She had full control, but if she ever just let her body move on it's own, it would default to being an actual mare, and not a human girl, which Jeff found to be both interesting and worrisome.
But there was still the issue of her heat. Jeff had to do something before she ran herself over to the nearest horse ranch and raped their stallion. The thought of doing that was incredibly tempting too. Suddenly a voice came from the hallway, calling for her. "Jess! Jess! Jessica!" It was her Mom, also apparently Jeff's name now is Jess, or Jessica.
"Yeah?" Jess shouted back.
"Come down here, I got a surprise for you!" Called out her Mom from the first floor. Jess looked in her closet and found she didn't own a single pair of actual pants, only leggings and skirts. Rows and rows of skirts, dresses and gowns. The leggings literally were not even 5% of her closet as the rest all were girly clothes that did not include pants. Sighing, Jess removed her leggings and adorned a casual white skirt with a decorative lace detail along the hemline. She also found a tight, black crop top that showed off her belly button, but that's it, as she didnt have real breasts big enough, or in the right spot, to fill the upper part of the top. So it did hang a little loosely on her chest.
"Haha, I have a pair of massive udders, but no tits, how ironically sad. I bet I could fix that though..." jess went back to the Chronivac and gave herself a matching pair of breasts to her udders on her chest, and also changed her nipples to only lengthen out to full size when she is extremely aroused, and will remain more human sized all other times. Now that her top was filled to the limit with her new tits, Jess excitedly left her room and headed down the stairs, all on her tip toes that had not only fused together and hardened in a hoof-like shape, but also kept their human features. They now make an audible clopping sound on the hardwood floor though.
Jess met her mother in the living room with total shock on her face. What she saw was her mother having a similarly shapped body as herself, save for the massive testicles and horse cock hanging from her crotch and behind her udders. She could see it all as the miniskirt her Mom had on didn't cover literally anything. Jess did also note that her Mom still had a mare pussy as well, meaning she was, at simplest, a hermaphrodite. But damn did Jess ever want her own Mom to fuck her with that impressive log. But she quickly shook off that impulsive thought.
"What did you want to show me?" Jess asked, distracting herself from staring longingly at the crotch of her own Mom.