"Someone like you shouldn't get away with this. I wish you were like me, then you'd know what it's like to get violated." This was Sarah's second wish, so it was granted to Jon.
Right before Jon's eyes, he watched as Sarah changed into a guy. She still had her own face, although it was much more masculine, but the rest of her looked almost exactly like Jon. The same short brown hair, the same slightly muscular build, everything.
Sarah looked down at himself in shock. It wasn't possible, was it? He touched himself between his legs and felt his penis. Oh, god, Sarah thought. I've got a cock!
Jon heard Sarah's wish, so that meant that she must have been touching the stone. But why was it granted to Sarah instead of to him? Was it malfunctioning? He hoped not, that would make it twice as dangerous.