An amalgamation of vulgar txt speak and military jargon; an acronym for "What the fuck, over?"
A response to a non-sensical statement or non sequitur, not used in face-to-face conversation.
A phone conversation...
Person1: So, then he says "Well, boss, I'm glad you finally decided to go ahead with my idea."
Person2: His idea? WTFO?
Person1: I know, he is totally delusional.