Likely offense: Informally introducing you to her partners via her orgasms

If her neighbors didn't already know who she was dating last year, they were undoubtedly clued in when they overheard John Mayer exclaim, "Your body is a wonderland, Katy!" during sex sessions. Perry can't seem to keep the volume down—reports say she played loud music and knocked boots with her now-ex Mayer at all hours of the night. We hear enough of Perry's voice on television and radio—no one needs to hear her hit the high notes at 3 a.m.