AITA for telling my fiancee to block her boy best friend

My fiancée has been friends with this guy for a couple of years. And the first time I met him, he playfully grabbed her neck. My girlfriend then told him he shouldn't do that and it clearly bothered her. When I saw that I was angry but I let it go.

Two weeks ago, she invited him to our engagement party between friends (she's only recently became my fiancée). During the party she gave him her gallery, thinking that there's nothing see (since she has a private folder) but apparently she missed a pic or two. So yeah, this guy saw my fiancée's intimate pics, he didn't click on them or anything and instead scrolled fast away, but it still stands that he saw them briefly. After seeing them, he continued scrolling instead of stopping, as if he was hoping to stumble on something again.

He also doesn't seem to learn, he often touches my fiancée, and often she will tell him to not do it but he will end up doing it again. I'm very against some other guy being physical with my fiancée. Moreover, it's not the first time he stumbled upon nudes in her gallery. Apparently he went through her gallery once before without her knowing, and he admitted he saw some nudes. How could he have been so sure that there wouldn't be any this time around? Either he's stupid or clearly there's something.

This guy has disrespected me enough and I told her he has to go. Either he leaves or I do because I will not tolerate her being friends with this guy.

This hurt her very much but she told me she will block him, I feel really bad because she cried and she must be feeling pretty depressed, but I won't change my mind.

Btw he has a girlfriend, but I find that to be irrelevant because even if he wants nothing romantic with my girlfriend, the fact is that he's disrespecting me. At least that's my point of view, maybe I'm just an insecure and controlling idiot.