"Oh wow," was about all Jacob could say then. His sex fun had gained him more than he ever imagined could happen, or be so real. As he combed his fingers through the spreading as thickening black fur, he felt shivers of joy and delight. His penis was on the move, it inching upward to where Jake knew he would have his very bullish sheath. It stopped moving when coming to just an inch below his furry navel. The sheath felt like a long tube covered with fur, what was inside the sheath felt as somewhat stiff, he having seen the bulls mate, their cocks emerge out the sheath some six to ten inches being flaccid, but extremely sensitive.
Jake fondled his changing sheath to get his cock standing flaccidly rigid, similar to what a bull has to seek for the warmth of a wet bovine labia. He stroking the pink penis made it stiffen. When Jake pinched the tip of his half-erect bull like cock, the cock stiffened and speared out from the sheath to stick out some twenty inches of sexual male meat.
With his changed cock standing fully erect, Jake began stroking of it, wishing he could masturbate it, wanting to see how much ejaculate came from a future mating. After six times with both hands clamped around his mighty shaft, he felt his balls churn and gawked at the resulting flood. Jake moaned as with each of three mighty ejaculation surges, his genitals produced thin pre and pearls of semen, the pearls reminding him to grandma and her tapioca pudding she made so well.
Just then, as the third surge slacked to a dribble, the sexual functioning urged greater changing to commence.
Jake literally jumped up as fell back to lying on his bed as both of his legs got massive cramping. Stern muscle cramps raked up from his feet through the calves, to the thighs, making Jake grit his teeth due to the intense painful agony. The cramps were a portion of how human legs would need to conform to being bovine hind legs, but Jake only knew he was in hellish agony and dared not yell for help.
Tears and gnashing of teeth, as muscles twisted, conforming to their new purpose and manner of walking with heels held high being strong hocks, and feet elongated, ending in cloven hooves.
"Oh please, please stop this awful pain," Jake groaned as begged, but the pain began moving into his buttocks, as tweaking the end to his spine.
Somewhere among his moans and groans the limit of tolerance to pain was reached and Jake fainted. His fainted was a manner of granting such as he some mercy from the pains shaping his legs, the buttocks, as sprouting and growth then of his bullish tail. Worse too, was the internal changing, the four stomachs and his skull, jaw, and teeth falling out, replaced by bovine teeth, as all was quite painful.
When it was near dawn, the first rays of sunshine peeking over the eastern hills, and Jake awoke, as rolled up to a sitting position at the side of his bed.
As usual for Jake when he would awaken, he would yawn and stretch his arms, interlacing his fingers and work a rotating of his shoulders. He then would jump up and off the bed to stand and begin more torso stretches, but this time when he leaped to stand, something had changed. The jumping up from off the bed, made the bed boards snap due to the increased weight of the sleeper. As Jake turned to look back at his broken bed, he found his stance troublesome. Human feet where not his style of feet, as hard cloven hooves found the hardwood parquet floor of his bedroom as quite slippery a surface to stand on or walk on.
In that scary instant when he lost his expected footing and upright stance, Jake toppled over forward, landing on furry hands and his butt high up in the air, as hind legs struggled to not spread wide apart.
"Oh holy cow," was the usual phrase what came from Jake when something scared him. This time the word cow took on a strange reality, and not thinking of milk, but he became mesmerized with want to sniff and lick the vulva of a cow. In that same sudden moment of sensual thoughts his cock protruded out its furry home and this too startled Jake.
Slowly and with caution, Jake reared his changed self to a standing position. He looking across his bedroom at the full length mirror attached to the back of his bedroom door, he saw then not an athletic young male human, but a sexually endowed young male Minotaur!