You might be a demosexual or something along those lines. There's nothing wrong with it, there are many people who do not feel immediate desires when seeing a person and who need some quality time together or special situations and relations and roles to feel a desire for physical intimacy. I, too, get turned on by "the story" and my fantasies about it and feel completely bored when looking at sexual scenes alone. So, for me normal movies are actually much more sexual than porn