Somebody who is addicted to Guitar Hero. They play it so much that they may have memorized some of the songs. Possibly can play eyes closed, backwards, upside down, if they are right handed they can play it lefty (and vice versa), or some other way that most people cannot do. Have beaten all levels of the game.
Sara: "Hey want to go catch a movie later?"
Jim: "No, let's just play Guitar Hero!"
Sara: "You just played it 2 hours ago."
Jim: "Umm more like 2 1/2 hours!."
Sara: "You are such a guitaraholic..."