Attracted by the noise and action, Bender fails to realize that the party is open to all, and attempts to keep a low profile as he worms his way to the bar, trying to pick up from conversation what exactly this shindig is for.

He mentally prepares a set of elaborate and fairly transparent lies to try to wheedle some free drinks from the bartender, but is pleasantly surprised when he finds that the bar is open, and there IS no guest list to pretend he's on.

Holding a large, cheap, strong drink in either hand, he yells triumphantly, and spends a while dancing in a particularly bendy-armed sort of way.