My Fiancé thinks I’m a freak for loving incest

I’ve been in a relationship for 3 years and it’s been great so far but he’s not into incest. I know he doesn’t feel the same way but I find the idea unbelievably sexy. I told him once and he really didn’t like it. I like women and I know my brother is always attracted to me. When I told him he thought I was being serious and thought I was a freak. I asked him if he ever thought I was hot and he admitted it and it really turned me on. I regularly have incest porn in my browser history and I’m afraid he’s going to find out.