Jon looked down to find that his penis was growing in length.
It was also becoming limp, but for some reason still felt like it was erect. Jon thought, given his current state of arousal, that his penis should be fully erect, no matter the size. And it did.
"What the..." Jon was amazed to see his dick rise at command. He was about to experiment further when he just didn't feel right between his legs. It was feeling a lot more sensitive.
Jon moved two fingers and put them between his legs. To his amazement he found what could only be a vagina. And his penis...
He brought his attention back to his penis and thought that it should be limp again. It went. Then he thought it should be smaller. It was. Longer? Got it. Thicker? Awesome.
But the wish was to fuck himself...
He envisioned his penis extending and wrapping around his leg like a snake. And it did!
"Holy crap!" Jon was amazed at the rock's interpretation. He had both a vagina and a fully controllable and malleable penis. He could literally fuck himself...
