Julie Powers [the belle of the ball] shows up to clarify the theme is Day of the Dead.
Okay, so maybe even the hostess is barely participating in the theme herself, but:
1) Shut the fuck up, Pilgrim.
2) OMG WHO CARES WHAT A CUTE OUTFIT.
To get this look, coordinate a strapless, multi-tiered party dress paired up with skull-printed tights and white maryjanes.
Optional: Round-framed glasses, a glass of wine, and a generally negative disposition.
[Scott Pilgrim vs. The Universe]