DEREK: "I met a woman last night."
MEREDITH: "You met a woman last night."
DEREK: "I'm telling you this because we don't keep secrets. I don't keep secrets. Nothing happened. She was pretty. I noticed. And we talked."
MEREDITH: "You met a woman last night."
DEREK: "Yeah."
MEREDITH: "So, should I be worried or something?"
DEREK: "Should you be worried that I met a woman? No. Should you be worried that, for me, flirting with that woman was a highlight of my week? Yeah, you should be worried."