"Come here sweety," the horse-girl says with a sympathetic voice, helping you to your feet. You stand uneasily, your large furry diaper hanging down past your knees. The warm manure rubs against your cock and balls, making you erect once again. She pulls out a large bottle about the size of a football, with a large rubber nipple on the top. It is full of a yellow, creamy milk-like substance.
"Drink this." she says, pushing the nipple up to your mouth. You try to protest but can feel your stomach expanding. You hesitantly accept the nipple and suck in several gulps of the sweet, creamy substance. "It's horse milk", the girl says, smiling slightly. "It will keep you from shitting so we can get you cleaned up."
Almost immediately the swelling sensation in your bowels stops. "Tha-thank you," you say uneasily, catching your breathe from everything that just happened. Your face turns red as you realize that you are standing in a dirty diaper that you had just cummed in next to a beautiful, horse-featured girl. "I, I don't know what happened. I just put it on an suddenly it—"
"I know." She says, smiling widely. "I was surprised the first time I tried it on too. But I found that the changes were definitely worth it. And it's really nice having to be dependent on someone. Let me help you get cleaned up."
You try to protest, but she turns and takes your hand, leading you out of the room, her dark blonde horse tail swishing behind her. Walking is slightly uncomfortable, since you have to keep your legs spread to accommodate the massive diaper between them. Instead of leading you to the front of the store though, she leads you back to a metal door that leads to the back of the shop. As she opens it you realize that it leads outside, to a large backyard behind the shop. The small field is surrounded by a metal gate, like what you would see on a coral. Part of the yard is covered by metal roofing, and there is a dirt floor here with a water trough and some other supplies. There are several animals in the yard, including goats, sheep, donkeys, and a few horses.
She leads you over to an area under the roofing that has a metal railing about waist high. "Before we get started, I'll need you to pay for the diaper. The next part is kindof... permanent. It costs $350, that's not a problem, is it?"