What is B'n B'ing?
To take a person to a Bed and Breakfast (Hotel) for the purpose of sex. The standard course of action with a Mistress, or Escort, that is visiting a Hotel where breakfast is served. Also may be used to indicate that the entire night was spent until breakfast, but not necessarily at a Hotel.
Man 1: Where'd you go last night with that girl from the club.
Man 2: I B'n B'ed the bitch.
Man 1: (Calling Man 2) What's up G?
Man 2: Can't talk holmes, I am B'n B'ing someone.