i have a few but their mainly just party games like pick out 5 random players dressed at guy characters people wanna slash and have them play twister, i can make 500 cards and we can play a yaoi/yuri based dirty minds. a game called mail call which is similar to musical chairs, i can design a yaoi/yuri based apples to apples but that might be a lil hard for 50+ people, and maybe i can think of a few contest games for prizes, they will include plushies, dolls, dvds, mangas, candy.
then maybe a pull the straw game where, in a cup full of straws of a certain color, a couple with matching straws are subject to fangirl service and will do what it takes to entertain (limited tot he basic rules of the con) most of these will be for 18+ but i'll try to think of a few more games for the minors.
also if were WERE to have it yuri based as well as yaoi, we need someone to handle the main yuri games because i know nothing of it