You're right, it does make sense--especially since he is so repressed. He can't possibly think of himself having sex with a man with whom he actually has a relationship of some sort. But I still maintain that his sexuality goes beyond gay or straight since he identifies with his sister when he's fucked. It's just very complex. I certainly wouldn't call him straight by any means. But he's too easily aroused by his sister to be completely gay, either. This is why I like the word queer. It fits him perfectly without having to label him one of the other. I consider myself the same way.