Someone who belongs in a loony bin but with the added subtle implication that even when a person appears fully functional and sane in the world that the truth can be entirely otherwise.
As I sat at my computer workstation on the other side of the wall from where the shrieking mentally ill prison inmate was coming entirely unglued, performing all of my workplace tasks without difficulty, a novel question popped suddenly into my head: just who exactly is the loony binner?
Where one person (usually female) is not permitted to have an orgasm alone (e.g. through masturbation) unless permission given by their significant other, Master, etc. Often used in D/s relationships. Very hot!
Girl1: Why are you acting odd?
Girl2: I'm so frustrated and can't concentrate. My bf has cum banned me and I won't see him for another month