SO triggers me with aggressive sex

So I've been sexually assaulted by family members when I was 5 and again repeatedly when I was 7. I was then raped by a Kappa while in college at 21 years old. I have really bad PTSD and have worked hard to seek help to deal with the dreams, drug use and triggers.

Me and my SO have a 9mo son together and we know everything about each other. We've known each other for over 10 years and took some time apart. In 2014 we had a sexual experience that triggered me bc it was unexpected (to me). He got really aggressive and violent during the sex. I clocked out completely and didn't talk to him for 2 years. After going to therapy and getting back in touch with him we conceived our child.

Here's my problem: he seems to only want to have aggressive, demeaning sex. Each time I give him head, I turn into his dirty slut (he calls me this and wants me to repeat it) Throat grabbing, gagging etc.

I asked him what kind of porn does he watch and he admits aggressive porn gets him off.

I love him and he's such a gentleman, but this is really not okay for me. Any advice on how to bring this conversation up? We're in the process of moving in together and I want to discuss it before it begins to make me hate the thought of him touching me.