A short paddle with the word yaoi writen on both sides. It is meant to hit you on the ass to show how much of a fangirl you are or gay/lesbian at a anime convention. Usually you are asked first, if not you have every right to hunt them done and get them banned form the convention. Usually done by fangirls or fanboys.
One side is the soft core side, which is meant to be used softly. The other side is the hard core side, which is meant to used more roughy.
It was first invented at Ota-kon, a anime convention in 2002-2003. Due to fangirls running around and hitting random people without asking, it has been banned at Ota-kon since then.
Person1 "Soft core or hard core?" *holds Yaoi Paddle up*
Person2 "Whut? Aw hell no. No Yaoi Paddle."