a woman or man that, after agreeing that their girlfreind or boyfreind can enjoy an evening out with their freinds, begins to nag and make a huge deal out of it. This is an effort to munipulate the person from going out and having a good time.
guy 1: Man, I thought Johnny was gonna make it to the game. What happened?
guy 2: I stopped at his place to pick him up and his old lady was nagging him pretty hard. He said he was out.
guy 1: she's a plan eater.