Harry finally gave into the instincts that were pressing at his mind and moved in behind the Zebra mare. She gave him a smile as he moved in close and pressed the tip of his cock against her opening, placing his hands on her back as she brayed lightly.
"Are you sure you want this?" He asked as he paused a moment, his human side was showing through a little and he wasn't sure if he really was ready for this. "I mean, you're in heat, what if..."
"I don't care about that..." Vicky said as she looked back at him with a smile. "I've been craving this ever since it started... I want you to be the father. Please, just take me, impregnate me, I don't care, I'm your mare and I want to bear your foals. Go ahead, mount me you handsome stallion stud."
Harry didn't need any more convincing as he thrusted deep into the woman and she brayed loudly. The horse within Harry took full control at this point, driven more by instinct as he neighed loudly and thrust faster and deeper into her. The horse side of him was now fully in control as he gave into it fully.
There was something exhilerating about the animal mating to the two former humans. Harry almost felt like this was what he was meant to do, if they weren't going to be human anymore then what was the point of not being the animals they were turning into? The horse mind was slowly starting to push out his human side as he lost more and more of his humanity with each thrust.
Beneath him Vicky was going through the same thing, though she had already given most of her mind up. She didn't care about her human life, it had done nothing but give her pain and suffering, she wanted to be a Zebra more than anything, and she couldn't wait to enter stage 6.
Harry let out a loud neigh as he thrusted one last time into Vicky and cum spurted from his cock. The Zebra woman's vagina clamped down on him and drew out more of his sperm before he pulled out of her, breathing heavily.