A girl that enjoys anal sex, sometimes even over vaginal sex. This is usually a secret preference, and not advertised by the girl, to avoid jokes and to protect her "reputation" as a "nice" girl.
She'llnever admit it, but I've heard that she's a Backdoor Betty!
12 step recovery jargon referring to someone new who talks about how great life is, now that they'resober. Usually meaning that the person is out of touch with reality.
The new guy seems pretty happy for a dude who has no job, no money and no family. He must be on a pink cloud.