Outside the barn door, Thunderbolt snorted and shuffled her hooves restlessly. From within, the scent of the mare she was to breed filtered through the wooden walls; a combination of whinny and whine escaped her throat as it made her already aching cock throb even harder, more precum dripping down to puddle in the dust. She was the farm's best stallion; this was what she was made for...right?
Thunderbolt snorted again and shook her head in confusion. Hadn't there been a time when she had lived...somewhere else? She did remember her owner bringing her here to the farm in a trailer. And before that...there had been...another place. Somewhere she had gone...to learn? But that didn't make any sense-- owner was teaching her everything she needed to know, like the different gaits, how to jump, how to pull a carriage... Except that owner had been there too, living with her at the learning place, in a little room.
And owner had made her listen to something, a special music that had made her mind feel all fuzzy and sleepy, and had taught her how to be a stallion. Except that didn't make any sense either, because she had always been a horse...hadn't she?
Thunderbolt tried to concentrate against the aching of her cock-- it was so hard to think when she was hard. Was there a time when she had been...not a horse? When she had been...like owner. Maybe if she thought about it really, really hard, she could remeb--
The barn doors creaked open from the inside. From the shadows of the space within, the mare whinnied in anticipation. All thoughts of a former human life were washed right out of Thunderbolt's head as she trotted inside, eager to get to work.