There are people in some parts of the world who find it disgusting that anyone would eat a horse, but it's happening more than ever, and most people who still eat meat are getting a lot less picky about where it comes from. You go ahead and flex your hands while you still have them, displeased that you will never experience grasping something or separating your fingers after today. But the first thing you feel isn't in your hands, it's in your maleness!
Your balls are throbbing, swelling, and making you hornier than you've ever thought possible. Your dick pounds erect and begs you to touch it! You wrap a hand around it and notice it's more than an inch longer than it used to be! Pleasure surges through it from your touch and you can't stop stroking after you start.
"What the fuck did you do to me?!" you demand, unable to accept that you are pleasuring yourself in front of complete strangers, and yet unable to contain your arousal.
"We've got to make sure your reproductive parts are in working order throughout the transformation, because you are going to be bred very intensely as a stallion. Might as well relax and enjoy it, you're going to have a whole lot more to play with soon enough!" the doctor answers enthusiastically.
Sure enough, your dick starts to widen and elongate even while you're holding it. You can't help but feel a little more manly at first, watching your member grow until it's the largest you've ever seen. You have to admit you were curious about what it might be like to be actually hung like a horse! The base of your penis gets anchored to your belly by a sheath of flesh, which feels strange, and then your penis changes color in places until it's a mix of black and pink. The head flattens, looking bizarre and inhuman, and the size of your penis means you soon have to hold it in two hands to pleasure more than just a tiny part of it. You find an awkward ridge around the middle of your shaft and find yourself curious. "What's this?" you ask yourself, bringing a hand down to tease it. You moan instantly, feeling arousal throughout the strange appendage.
"I see someone's already found their new medial ring!" says the doctor, watching you eagerly learn to provide yourself with enjoyment using this new equine shaft. The head flares out like a trumpet, which disgusts you, but you just can't slow down at all or look away. Your body tenses, and fluid pools inside the base of your groin. A huge wad of semen rises all the way up your lengthy shaft and splatters forward in front of you. It happens again and your eyes roll back in your head. You think you're about to black out! You don't, though, and eventually you come down from your sexual high. Your dick has flopped over in front of you and waves limply while dripping yellow cum, and you can see the floor is wet and sticky with a gross, chunky excretion. You realize you've just had your first equine orgasm, and your life span will depend on having a whole lot more! What comes out of your testicles now is just for making foals, and yours are going to be food for human beings, just like you will be eventually when you are no longer a reliable breeder. You grab your dick again and hold it up in front of you while it softens toward your sheath. It's wrinkly and nasty and doesn't belong on a human at all, but you're stuck with it from now on, and at least you know it can make you feel good. Some part of you even wants to find out what it might feel like inside a mare's pussy.
Another fluid buildup shifts inside you, and before you're even realized what's happening, a surge of pressure flows through your shortening shaft and jets out with the force of a firehouse. You're peeing! And you don't even seem to have control of it.
"Uh, my bad!" you say while the flow is still gushing. You sound oddly apologetic for someone who's being stripped of his human life against his will. But you're incredible embarrassed by what's happening, and you can't think of anything better to say!
"No worries," says the doctor, "we'll clean that up. Incontinence is sometimes a temporary or permanent side effect of the serum, and horses aren't expected to care where they let loose anyway."
It's supposed to be comforting, but it's just another reminder that you're on your way to being just another animal, looking dumb and standing in your own piss. It's then you feel a cramping in your...