Hmm, you think someone would have at least come dressed as a katamari ball in that group. If anything, that would have been the easiest costume...just stick a bunch of useless junk around your house onto your body.
And the cosplay kings costume is nowhere near as tight as the game's king...seriously, the king in the game is either hung or stuffs *shudders everytime theres a cutscene with him in it*