Personally, I'm a pedophobe. Perhaps I could resist waterboarding, but toddlers could get me to confess to anything. So, you will never see sexual contact with children in anything I write.
In at least two of my current stories, however, I am exploring the idea of incest involving consenting adults. Even there, the characters are exploring the very idea in one case. In another, though, I find it difficult to assume that it's a horrible idea, between a 34-year-old child who is a high-level sex worker, and a 59-year-old disabled parent.
It occurred to me that Robert A. Heinlein wrote quite a bit about things that were technically incest among adults, as well as some cases where the sex acts were among people who weren't biologically related, but where one had been in loco parentis. I'd be very interested in getting comments not only on the stories themselves, but on the ethics involved.