True narcissist

So me and my ex got a child together so I'm trying to be his friend since my feelings for him are pretty much gone so it's not a big deal now. I mean we still flirt at times but we're both single and it's nothing serious because he knows I don't want to be with him and it's all fun. Well he said he was bored so I sent him a selfie of myself and said feel better now and he goes no because your clothes are still on. Well I told him I didn't like him talking sexually like that to me and he said well if all we do is hook up shouldn't I talk sexually to you.. (First off we haven't done anything since our split 6 months ago and secondly I never said I wanted to hook up with him!). I told him this and he said well I don't care if we do or not and I said okay and he goes it was just a joke get over yourself (the clothes thing) and I was like why you being a jerk because I just asked you not to talk sexually to me and he said because I'm being honest and you're overreacting to a joke just like when we were together (never even did that when we were together because we were together so sexual stuff didn't bother me at all 🤷‍♀️). So I asked him why he gonna bring up the past and he said well stop bringing up old behavior and I'm like all I asked was for you to just talk to me like a normal person. He basically begged me to be his friend because I was hesitant at first and then he gonna act like this like wtf.. Btw the flirting isn't usually anything sexual. It's usually just playful flirting. I know how he acts and this is one of the reasons I was hesitant to try being friends because we didn't have a good relationship when we were together and he always made me out to be the bad guy in the relationship (super toxic behavior) so we ended it and now even though we ain't together he still tries to make me look like the bad guy.. It's crazy how some people never change. Smh. Should I just leave it to us just talking about our son? I don't think I can handle this crap again. This is the first time he's been an ass like this since we started talking last week after just keeping contact between each other pretty much non-existent for the last 3 months.