(Rachel has found a receipt from Monica and Julie's lunch together)
Monica: Look, when it started I was just trying to be nice to her because she was my brother's girlfriend. And then, one thing led to another and, before I knew it, we were... shopping.
Rachel: Oh... Oh, my God!
Monica: Honey, wait. We only did it once. It didn't mean anything to me.
Rachel: Yeah, right. Sure!
Monica: Really, Rachel, I was thinking of you the whole time. Look, I'm sorry, alright? I never meant for you to find out!
Rachel: Oh, please, you wanted to get caught.
Monica: That is not true!
Rachel: (about the receipt in her coat) Oh, so you just sort of happened to leave it in here?
Monica: Did it ever occur to you that I might just be that stupid?