When a player in an objective-based multiplayer FPS game makes a point to position themselves to an area of the map near the opponent's spawn, shooting passersby in the back. This is done with the express purpose of preventing players from getting to the objective, sometimes the "Black-Wolf" will position themselves near a potential spawn location long before the opposing team has started spawning there.
The act of a girl putting her head between the legs of a boy who has pulled his pants down and covering his penis and pubic area with her head
My Father once said to me "Son, marry any girl who is willing to start big bad wolfing with you, take a picture of it and whore it out for karma on Reddit"