When your vibing with a girl, shes dancing up on you, your flirting, you try and make a move, and she denies you. You thought she liked you enough to hook up with you, but she doesnt. Stand for "Mind game player" She makes you think she's interested, but she's really not. Calls you her flirt friend, her "brother", etc.
I was flirt with her all night, but she wasnt tryin to hook up...that damn MGP
She was lying on me last night, and when I went it she moved back. She nothin but a MGP.