Erik wouldn't do anyone, not even Christine.This is why I don't read fanfic. He hates it, and getting him angry is the last thing I need. I know fanfiction isn't known for realism, but the only reason Erik would ever touch Raoul would be to kill him. He's not exactly the banging sort.
Then again, he's I wasn't too impressed by the movie. I think most of the Erik/Raoul fanfic is wish fulfillment based more on the actors than the actual characters themselves.