What turns you off when reading Yaoi?
For me it's when the uke is confused/hate/reluctant to be on the bottom. Because usually when the uke is like that, the seme will push the uke until he's willing to submit -_-
The highschooler side couple in Honto Yajuu is a good example of that
I very much prefer a gay bottom uke that's not afraid to bottom and an understanding seme please :)