Despite the staggering pain, Ryan did his best not to cry out. Heat washed through him, and it felt like his skin was being stretched to bursting. Yet behind the pain was a sense of increased mass and power. He focused on that, clenching fists as they grew heavier and harder, and arching back as his legs throbbed and thickened. His face was pushing out, and part of him wished he could see the transformation that was going to cost him his intelligence and memories. Now he understood Circe's warnings - as a horse all the way, he would not appreciate the change, or even be aware that it had ever happened. He forced that thought from his mind, determined to experience the transformation, good or bad, and appreciate it.
There was pressure in his skull as his head altered shape, pressing in and shrinking his brain to fit the smaller space, and his jaw thickened. Somewhere along the way, pain faded and pleasure began to swell. Balance shifted, and his legs pulled in a twist that threw him down onto four legs that ended in massive hooves. Something about the sensations were confusing, but Ryan simply arched back and reveled in the intense waves of pleasure that now washed through his body. The mass and power of a Clydesdale stallion filled his awareness, and he shuddered as he came erect rapidly, pressure in his swollen testicles building rapidly. The transformation appeared to be coming to and end, and he guessed that his awareness would be obliterated by the sexual release he was rapidly approaching.
Ryan held back as long as he could, but the immense need to cum finally became too much, and he whinnied in climax as his equine seed shot between his legs and splatted the ground. Panting, the former boy gradually drew in the musky odor of his equine self, and felt his ears twitch high on his head. He relaxed his fists, still clenched... huh? Ryan's eyes popped open, bringing in a confusing view much wider than he was used to, but stripped of most color and split by a massive muzzle. Twisting his head, he discovered that while his powerful body was indeed that of the Clyde stallion he had expected, the golden fur swept up a powerful humanoid chest and across thick, muscled arms that ended in three-fingered hooflike hands. He felt his chest and face - a full Clydesdale head sat on top of the body-builder shoulders.
Circe chuckled when he turned to look at her, amazement obvious even on his equine features. "It is not too late to finish up as a normal horse, if you are disappointed. However, I thought that turning you into a full animal might be a great waste of a willing volunteer." She walked around him running her hands over his hide and inspecting him as she would a horse for sale. This included his genitals and even his teeth, all of which he endured without complaint. When she was done, she stepped back and nodded in approval. "I like you, boy. You had an unusual desire and the commitment to fulfill it no matter the cost. So I give you a choice. You can remain like this, still a work horse with no voice, but with arms, hands, and your mind intact. You will live as a beast with the beasts, your life devoted to labor and service. Plows, wagons, and mares may grow old to a human mind. As a second choice, you can finish up in body and soul, becoming the animal you sought to be while still remembering your past. You will be in essence a very smart animal, you actual place in the universe altered, and as true beast, find easy acceptance of your new lot in life. And finally, I can do a total transformation that will strip you of your memories and intelligence, leaving only the horse."
"If you wish to stay as you are, kneel before me. If you wish to be a beast with your memories, hold your arms behind your back and keep your head up. And if you choose to be a true horse in all ways, also lower your head."