When people (typically women) in two adjoining rooms, such as in a hotel, motel, or house, are partaking in sexual intercourse and begin to compete to see who can have the loudest orgasm and to prove who's man is more sexually pleasing.
Guy #1: Dude last night me and my girl were at a hotel and she got into this crazy orgasmoff with the girl in the next room!
Guy #2: What a coincidence! My girlfriend did the same thing last night too!
Guy #1: Wierd!