When you get right down to it, it's a couple of good jokes and Lumpy Space Princess that makes 'The Creeps' memorable. Doesn't seem like much, but man is it played for great effect.
It's a riff on "Clue" with everyone attending a masquerade ball, complete with masks and character names - really, some of these are just priceless: Prince Hot Bod (Finn), Randy Butternubs (Jake) and Guy Farting (Cinnamon Bun) - plus a healthy dose of LSP. Her tirade over her breakup with Brad is hilarious (keep in mind, this is a dude voicing the character). There's a twist ending to all of this that seems pretty obvious, but also fits well with the show's sense of humor.
It's so inane, but I love it.
8/10