Hes driving me crazy wanting freaky sex again

My ex is back and right back to his messed up fantasy list which nothing is normal at least to me. I think he only came back because he wants to finish it with me. I asked why he just didn't work on it with his ex. He answered with "I only want to do this with you" why couldn't we just have normal sex IF I even decide to? I have dodged seeing him because I don't want sex with him after only 4 days of talking after being thrown away for 6 months. He said he walked away from the drama. Why does he keep coming back? Is it only the fantasy or does he have feelings?