The Big Bang Theory Season 1 Episode 3: "The Fuzzy Boots Corollary"
When Leonard witnesses Penny kissing a guy in front of their apartment, he is hurt and feels "rejected." The guys try to convince him to ask a girl out at work and when he's rejected by Leslie Winkle, he is even more depressed.
Leonard: No, I'm done with Penny. I'm going to be more realistic and go after someone my own speed. Raj: Like who? Leonard: I don't know... Olivia Geiger? Sheldon: The dietitian at the cafeteria with the limp and lazy eye? Leonard: Yes. Sheldon: Well, I don't think you have a shot there
Sheldon: I have noted that Leslie Winkle recently started shaving her legs. Now, given that winter is coming, one can only assume that she's signaling sexual availability. Wolowitz: I don't know. You guys work in the same lab. Leonard: So? Wolowitz: There are pitfalls. Trust me, I know. When it comes to sexual harassment law, I'm a bit of a self-taught expert. Leonard: Look Howard, if I were to ask Leslie Winkle out, it would just be for dinner. I'm not going to walk into the lab, ask her to strip naked and dance for me. Wolowitz: Oh, then you're probably okay