"Who are you gonna change first?" Karyn asked.
Jon thought about that, then pointed the device at Karyn and pulled the trigger, before she had a chance to protest. Karyn's body was bathed in an odd purple haze. When she was visible again, Jon saw that Karyn had turned into a guy! And he was wearing clothes similar to Jon's.
"Karyn? Are you ... are you okay?"
"Karyn? Why are you calling me Karyn? My name is Karl, Jon. Now, come on. Let's go play that new game you bought."
Jon couldn't believe it. Karyn really had become more like him. She was now the male version of herself and she (actually, he) now had the same interests as Jon too.
He dropped the device on his bed and went downstairs to the TV room to show Karl the new video game he got.