Am I an asshole for not liking my boyfriend having a specific female friend?

Context: he has been friends with her for longer than we have been together and she is apart of his friend group (only guys, and two other girls, one who is dating another in the group & her twin.) My issue is, she actively “gets around” with the other guys in the group, talks to my boyfriend about having 3 ways with some of the guys, had sex with one of them on an air mattress directly beside him while he was sleeping on the couch after a night out, admitted to having feelings for another friend who is in a relationship with the other girl in the friend group. And after some stalking, saw a collection of photos, one including her sitting up on my boyfriend lap posing for the photo at friend hangout. So AITAH?