Groupie or Moupie (male groupies), DJ whore, Stalker. Individual who follows the DJ of a club or a band in cult like form. Trustfund baby or wanna be industry person with no talent who feeds off the performer's fame in order to elevate their own worth. Delusional follower and parasite.
"That bottomfeeder was insisting she was on the guest list and demanded to speak the the band."