So I have my bf’s Facebook so I can get in it, he recently gave it to me.

I was looking in his messages with this girl, (I know her) and those messages were from the first week we started dating. He asks her what she’s doing and she says “squats to get my butt bigger” he says oh and “do they work?” She says “well I think they do, when I go over there (his town she’s not from over here) I’ll show them to you” and he says “ok then I’ll tell you if they’re bigger” in a flirting way. Help a girl out Idk if it’s cheating but it’s not right