As you examine yourself you come to realise that it's no fun having this body if you can't go out to the prom to show it off yourself.
Before you head off you turn awareness off so everyone thinks this is normal, as well as hook your phone up to the chronivac so you can take it on the go for more transformation fun. Now you head out, wearing the composite dress and with your new torso and legs.
You arrive at the prom seeing various teens like yourself dancing and socializing. There's many targets you want to swap with, both male and female. Over in the corner you see the two girls with your torso and legs, laughing away like there's nothing unusual.
You feel a desire to switch more body parts,maybe even clothing or personalities.