His massive horsecock slid out of its sheath as he rubbed it and ran her tongue slowly along the flared tip. It wasn't an unfamiliar sensation, but he wasn't quite used to an anthro horse, or Zebra in this case, giving him a blowjob. Still, it didn't feel unpleasant, especially with the feeling of her tongue rubbing against his shaft as she bobbed up and down on it.
Ever since he had started to transform he hadn't even considered having sex with a mare, but now he didn't care. His growing instincts were telling him to mount and impregnate the mare. She was in season, the smell of her heat was driving his inner stallion crazy and he was getting more and more willing to give into it.
Vicky smiled up at him as she took as much of his cock into her mouth as she could and sucked at it. He couldn't believe how good this felt, and he was starting to think more and more about mating with her. Was that a sign that he was getting closer to Stage 6? He had no idea, but he didn't have much time to dwell on it as he came and his seed spurted out into her mouth.
"Mmm... tasty..." She said and licked her lips before she backed up and turned around, pushing her tail to the side to reveal the leathery folds of her vagina, her pheromones driving Harry crazy. "Come on, take your mare big boy. I want you to breed me, take me like the mare I am..."
Harry paused a moment as he thought over what to do, he made a quick decision.