(n.) One possessed by an evil spirit; a demoniac.

LSD user acidhead address adherent adjust admirer aficionado alcoholic apply aspirant aspirer bias buff bug candidate chain smoker cocaine sniffer cokie collector coveter cubehead demon desirer devotee dipsomaniac direct dispose dope fiend doper drug abuser drug addict drug user drunkard eager beaver energumen enthusiast faddist fan fanatic fancier fiend follower freak glue sniffer great one for groupie habitual habitue hankerer head heavy smoker hobbyist hopeful hophead hound hype incline infatuate junkie lover marijuana smoker methhead narcotics addict nut pillhead pothead predispose pursuer putterer rhapsodist snowbird solicitant speed freak sucker for suitor supporter take to tripper user visionary votary wanter wisher yearner zealot