I look for ones that have a lot of chapters and where the characters fall for each other within a normal time frame. None of that 'its love at first sight for both of us and we lived happily ever after' stuff. Though I will admit that slow romance really bugs me. Basically, I look for a good, balanced timeline for their feelings to develop. I also......
Really, everything I would want to see in any other romance manga or real life relationships, but it doesn't happen (often). Mostly trust I guess? Strong trust between partners is incredibly sexy. Also, why I prefer yaoi over shoujo smut is because you can find cheeky, strong ukes. All the pretending and blushing by girls in mangas seriously annoy......

what are your favourite things to look for in yaoi