John was having an urge to do something with this woman. His was the first real feelings of an urge to procreate. That in the coming years would guide him to use his large and long penis as it was predetermined to be.
Even as he stood up the poisen pulsed into his veins. The building urge to have and feel a joining of his and her bodies' was his one and only thought.
Mary watched with a generous smile as her desiring lover was changing before her eyes.
John did not notice his changes as the blinding lust to have sex with this woman before him was all consuming. His skin was darkening minute by minute to become the black thick hide of the equine animal.
Standing up to be face to face with Mary John watched this woman begin to pop loose the buttons on his shirt. Her wonderous smile captivated him and he thought only now of the pleasure he was to enjoy.
Excited so much was John that even as his trousers hit the floor he stood with an erection growing now over a foot long. His blackened skin color was being hidden by sprouting thousands of short summertime hairs.
His shoes off he stood in jockey underwear ready to enjoy what his mind and heart held such passion for to do. He shivered and shudder of transformation down his body making him smile as lips and nostrils began to merge. Earlobes growing both taller and hairy moved ever upward toward the top of John's head as his skull changed to one of a true equine form.
Once in her bedroom Mary also prepared herself dropping off clothing till she stood before her changing friend.
Flopping over the end of her bed she offered to John a sight making him lick his lips with lust.
Stepping forward John placed his forehoofs on the bed either side Mary's shoulders. Folding them down he knelt on foreknees as his lips nibbled at Mary's face.
Out stretcched behind was a lengthening body and those huge pelvic hips of an equine. From deep within his groin was a sheath and stretching out from there now the size on penis like a Pony would have.
A little guiding help from Mary had his maleness entering her body. She moaned as this was for her a real perverted sort of pleasure. The thought of having sex with and by a aniaml born animal was beyond her possible consideration. Yet knowing that this was a man just an hour before seemed to make those worries vanish.
John was almost totaly changed to a colt horse when his first load spewed into Mary. As he was urged to try again from his sex drunk partner she watched as the final changed took his humanity.
Soon standing calmly by a yearling sized Morgan hose stood feeling the odd sensations of being a horse. Mary petted her friend his fear of being an animal never materialized. She wondered if the passion he and she knew together had reassured his confidence so that his mind just accepted the change as a part of learning to have sex?