A "superfan" someone that espouses the virtues of another individual in the face of any and all opposition.
Scene - guys at Hooters watching the game.
Earl: "Kobe has been throwing up bricks all night get him out coach."
Bill and Jim: "Its not his fault, he's not getting the assists."
Earl: "Why don't you guys get off his jock, you are a couple of Kobe nut huggers."