A scarfy is a pretentious indie or theatre kid, who would usually engage in activities such as eating their lunch in the photography room or spending free blocks in the "art hallway." They generally listen to horrible music which usually consists of acoustics too quiet to hear, extremely loud drums, and vocals that give you a migrain, which they may think are "deep" or "profound" but are actually complete and utter horse shit. They are characterized by the scarfs they wear year round.
Did you hear about David? Yeah, what a shame, 1 month of being in theatre and he's already a scarfy.