I’m having a tea party

Sheldon: Given that Saint Valentine was a third century Roman priest who was stoned and beheaded, wouldn’t a more appropriate celebration of the evening be taking one’s steady gal to witness a brutal murder?

Raj: The big-boobed weather girl on Channel 2?

Sheldon: I’ve been dreaming about going to the Large Hadron Collider since I was nine years old.
Leonard: Yeah, well, I’ve been dreaming about spending Valentine’s Day with a girl since I was six.

Penny: You actually put that in an agreement?
Leonard: Yeah. We also put in what happens if one of us wins a MacArthur Grant, or if one of us gets superpowers, or if one of us is bitten by a zombie.
Sheldon: He can’t kill me, even if I turn.
Penny: Is there anything in there about if one of you gets a girlfriend?
Sheldon: No, that seemed a little farfetched.

Leonard: What would you do if you were me?
Wolowitz: I would take Sheldon to Switzerland!
Leonard: Really?
Wolowitz: Yes, and I'd leave him there!

Sheldon: Hello.
Penny: Hello.
Sheldon: Alright, let’s dispense with the friendly banter, I believe you know why I’m here.
Penny: Well, I always figured it was to study us, discover our weaknesses, and report back to your alien overlords.

Raj: I’m going to have a me day. First I’m going to go to one of those spas in Koreatown, take a steam and get a massage. Then I’m going to stop at a pet store and get licked by puppies.

Sheldon: It’s you! I touched you!
Penny: Happy Valentine’s Day.