Raj: Where's Sheldon?
Penny: Date night.
Leonard: That can't be much fun for Amy. You know at work today he tried his first Redbull.
Bernadette: What happened?
Leonard: He chased a squirrel around the quad for a while. And then threw up in my car.

Sheldon: I remember the song! It's called "Darlin'" by the Beach Boys! Oh, thank goodness! I'm not crazy! I don't have to take a pigeon as my bride!
Leonard: There goes our shot at him living on the roof.

Howard: Don't feel bad. Some day someone will be throwing out your work, too.
Leonard: That someone was Sheldon and the day was yesterday.

Professor Proton: Can I ask you a question?
Leonard: Yeah, sure.
Professor Proton: Why do you put up with Sheldon?
Leonard: Oh, you know because we're friends.
Professor Proton: Why?
Leonard: Wow, you ask really hard questions. Look, I know he can be aggravating, but what you have to remember is he's not doing it on purpose, it's just how he is. But he's also loyal and trustworthy and we have fun together.
Professor Proton: You know you're describing a dog?
Leonard: He did bite me once. But in his defense, I came up behind him while he was eating.
Professor Proton: They hate that.
Leonard: Sheldon is the smartest person I have met. He's a little broken and he needs me. And I guess I need him too.
Professor Proton: Why is that?
Leonard: Boy, you will not let this go, will you?

Howard: I invented a game. Want to play?
Leonard: Sure.
Howard: It's called Emily or Cinnamon. I give you actual quotes I've heard Raj say, and you guess if he was talking to his girlfriend or his dog.

Leonard: At least listen to it through headphones. I'm trying to sleep, good night.
Sheldon: Boy. Taylor was right. Haters gonna hate, hate, hate, hate, hate.

Amy: Look, your anxiety levels are right in the zone.
Sheldon: Really? Oh, that's fantastic. No wait, they're dropping. Why are they dropping?
Amy: Because you're happy they're elevated.
Sheldon: Oh, that is infuriating. Oh look, they're going back up again. Terrific. Oh no, they're going back down.