You get home. Your girlfriend moved in with you and your parents a month ago so she'd be there an hour after local school ended, she worked as an intern for the elementary school your baby sister goes to. When she gets home you welcome her with a kiss.
"So you know that famous sex change company?" I ask.
"Yeah, what about them?" she replies curiously.
"They signed me up to test their body change app." You hold your phone out and show your girlfriend by temporarily adding one too many fingers to your hand. But a devious smile crosses her face as she snatches the phone from you and darts for the bedroom. you chase after her.
"You know, we could get into some kinky shit with this!" She winks at you as she closes the door. No longer worried, as she only wan't some sex, you nod in agreement "But only I can change you during sex. Take off your clothes so I can try my first idea!"