My ex catfished me

So, my ex boyfriend is impersonating a girl on snapchat to get other girls to send him nudes, then blocks them and posts them to his snapchat story.

My current boyfriend is okay with me talking to girls in a romantic matter so when I found out it wasn't a girl I was sexting with but my raunchy ex scumbag boyfriend, I instantly wanted to vomit.

Now he is posting my nudes to his story and calling me an internet whore!!! How would you handle this?? I'm having people report the snapchat but it's still shitty...

Edit: before you jump down my throat with the "cheater cheater" thing, my significant other and I are in an open relationship and he is more than okay with me talking/sexting/ messing around with girls