Jon's mom could see a change of expression in her daughter's face. The rock had chosen the easiest way it could think of to make Jon and Zoe walkin each other's shoes: exchange their bodies.
"Mom? What the hell are you doing here?"
"Zoe, I've been here all along. What are you talking about?"
"Why are you calling me Zoe?"
Jon looked down to the sudden realization that he now had Zoe's body. He heard a door slam and knew his bitch of a little sister had left in HIS body.