Every year Dragoncon manages to bring up a new surprise. So far as I can tell, for the adult-oriented costumers, the game is to come up with something that is as blatantly sexy as possible and sexual as hell that still does not get you thrown out of the convention or arrested. Given that the sexual mores get pretty damned relaxed during the Con, especially late at night in the bar areas, attendees have rung up some fairly imaginative changes on the nudity, sex and bondage themes that predominate among them.
(I put the masks over the young ladies' faces because I had heard that some attendees who cavorted about in sexy costumes one year and whose images were then shown on a DragonCon website had faced the possibility of some job losses. These young ladies might be wiling to take such risks and appear in public thusly attired, but I'm not willing to take it on their behalf.