Continue the erotic transformation story: 

The large Umbreon walked forward out of the clearing in front of the scared man.
"You're right about one thing, human," he said. "I'm going to turn you into a Pokemon. But I'm not going to use some elaborate transformation spell. I'm going to do it the old-fashioned way."

NAME_1's heart began to pound even faster. "What are you talking about?" he asked.

The Umbreon just grinned. "I'm going to do it the animal way. I'm going to breed with you."

NAME_1's eyes widened in shock. He couldn't believe what he was hearing.

"What did you say?" he asked, his voice trembling.

"I'm going to fuck you, human," the Umbreon said. "My seed will impregnate you, and you will give birth to our child. And you will be my mate, our kit's mother."