Maybe we like deviant fic like rape fics or hurt/comfort fics, because of an innate curiosity that we have to try and understand something that's so reprehensible and yet a common occurrence in our society today. One likes to know what the person feels in such situations, so we can understand their pain better. Also, there's the eternal hope that things will be better in the end.
That said, I love reading H/D, though I live in a world where homophobia seems to be the norm. I'm straight myself, but I don't appreciate people judging and commenting on things that they have no idea about like 2 people of the same sex loving each other.
So, I love exploring fics in the H/D universe, I guess it's the love and the freedom that's something I'd like to see in our world today.