A lifestyle that tries to duplicate/replicate a fantasy down to the tiniest details. Whether its clothing, hairstyle, lifestyle, food, personality quirks, etc etc. Its a very extreme dillusion. If Your concerned that you are one or living that way, dont worry... your concern shows your not one. A person living this life style cannot discern real life and reality.
A example is a anime fan who eats, sleeps, breath the lifestyle of zeon soldier.
David, a person who chose the fanatic lifestyle, sat at his table in his apartment that was modeled like a starships cafeteria