The way all of the 'die-hard fans' dress and act at Harry Potter premiers.
Looking like a replica of Ron Weasly, or Harry Potter, or even DORKTASTICALLY more so, an abstract character.
Reenacting scenes of dual from the movie, having every spell and step memorized, DORKTASTICALLY showing off your epic wand in public. (Even though it's a drumstick wrapped in black electrical tape.)
Talking with a terrible British accent, whilst ordering your slurpee.