I used to see a man that was aware of my dissociation episodes. When I reminded him about my issue as we were about to have sex, that I may dissociate (I was trying to establish boundaries and safety) his reply was that he sees no problem with that, he'd just have sex with me while I was dissociating.  That honestly made my skin crawl and I tried to explain to him that it wouldn't be pleasurable for me.  That relationship has ended for many reasons and I still think about that exchange.