Fabricating an embarrassing story to mask your non-attendance at an event.
Friend 1: Are you going to the Rozelle Flop Party Saturday?
Friend 2: Nah, it'll be shit.
Friend 1: Don't be a tight arse, whats your excuse?
Friend 2: I'll tell them i went home with a kinky chick Friday night, and she did me up the arse with a strap on dildo.
Friend 1: Ah, classic Lord Nelson.