Putting aside the aftermath for the moment, let's discuss the dorkiness of sticking a rubber ducky to your forhead.

Of course, it's not like anyone is going to notice. It probably doesn't rise far enough above the mean dorkiness-of-appearance quotient of Arisia attendees to make a significant blip.

In a sea of fat Klingons, elves with nasty skin conditions, Roseanne Barr lookalikes wearing chainmail bikinis and the like, a duck hickey ain't gonna register.