Context: I'm part of a friend group, where my best friend is seeing one of the girls and I am seeing another one.

They are being pretty serious and it's going well, whereas Y and I have agreed on seeing each other casually. For context, I have been to her place 3 times in the past week, the sex is absolutely amazing and she's being very attentive.

She shittests a lot, and everything is fun and easy. We're still seeing other people, as I have no interest in pursuing an LTR with her. However, the entire friend group knows that we're fucking casually.

The other day the group was out drinking, she got drunk and ended up making out with a random guy basically next to us. Every single friend has since mentioned that they found it awkward since I was right there.

I have mostly just brushed it off, but I find it pretty disrespectful. I have soft-nexted, but I still want to have sex with her since it is very, very good.

Question: Should I set boundaries verbally, e.g. saying that I found it disrespectful and then go about being just myself? I'm not thinking a big thing.

Or, should I just ignore it?

The last one just feels very cucked and out of character for me. She knows that I'm a very outspoken guy with a clear idea of what I want.

Is there other ways to set boundaries? I could withdraw attention, but I have already done that.