I've had that happen to me in non-flirting situations where people will say something like, you know so-and-so, and I'll go, yeah, so-and-so, and they'll be like, how do you know so-and-so, and I'm like, oh, crap, I don't know so-and-so, or they'll say, did you see this movie, and you'll go, yeah, I saw that movie, and you're like, oh, I didn't see it. Yeah, exactly, and you don't know it.