What sort of yaoi do you hate?

I know some people don't really care what sort of yaoi they read but there is always something you least like to read. I'd like to think I'm pretty easy-going and anything's good. However, I can not stand shotacons and student x teacher. Never. I despise it. I know some people love it, but I never will. (╬￣皿￣)凸
What sort of yaoi do you dislike? Or read the least?