Boyfriend looking at very odd phone?

Recently I went to use the internet on my boyfriends iPhone while he was in the shower. I got curious and looked at his browser history which showed what he looked at for the past week. Every day he looked at porn sites, which is fine...but what bothers me is the type of pornography he was looking at. He looked at transvestite porn, animal porn involving horses and even went on one porn website and in the search bar typed in his ex girlfriends name "Molly". This really bothers me and Im not sure what to do. I am not sure why he would type in that name. Perhaps it turns him on to see someone with his ex's name do sexual things and maybe he is still enticed by her. And the other porn he looked at was VERY odd to me. Why would he be looking at transvestite and she-man porn? Why horses? We have a great relationship and just moved in together. We have sex every day and I know he is an EXTREMELY sexual person. I just don't know how to handle this situation and wonder if he is some sort of "freak" or if he is just curious. Thoughts?