He had barely managed to stand up when the first part of the transformation took effect. He felt his head hollow out, something which was painful at first, but to his surprise wasn't too bad after a moment. From the roof of his mouth up was hollow, so he kept most of his mouth intact, but that's about it.
A sharp pain seared through him as a hole opens in the top of his head, and he falls back down. The functionality follows, as he becomes absorbent. A pair of leg holes appear in his cheeks.
He felt his size get reduced slightly, and his vision was blurred. He saw something blurred moving... before something was seemingly *in* his head. A strange taste was on his tongue.
A set of legs poked out of his cheeks. Just barely larger than a toddler. Something- Someone was inside him. He was not used to this feeling; There was a child sitting in his head, yet it didn't feel heavy at all.
He could taste the kid's skin... which worried him. He set the owner to always be a girl, so as weird as it was, he moved his tongue to check, coming in direct contact with a toddler-sized vagina.
He was already not happy with what had been done, and the transformation itself wasn't even done yet... And he'd have six months after this. He laid down on the nearby bed, deciding it'd be better to sleep through and avoid some of the changes.