Sweetie ... every night you don't kill him in his sleep, he wins.

I may be a bad waitress, but you're a bad person. Now, want to hear the specials?

Leonard: How about that? Sheldon's being reasonable.
Penny: Yeah, it's freaking me out. I'm gonna go.

Penny: Ooh, that looks like fun.
Bernadette: Maybe you should master glue before you move on to fire.

Penny: Just you wait and see. I'm gonna romance your freakin' ass off.
Leonard: That's beautiful. Is that Shakespeare?

Sex doesn't count.

Penny: Hey, how come you've never done anything romantic to celebrate our first date?
Leonard: Well, for starters, you've broken up with me so many times, which first date are we talking about?

Penny [to Sheldon]: Your food's ready.
Leonard: No, no, what are you doing? He's both happy and quiet. It's like seeing a unicorn and Bigfoot at the same time.

I'm not going to the mall with someone dressed like a dumb space bear.

That's right. My phone is just as smart as you guys.

Bernadette told me everything. Now you don't get the left or the right.

Leonard: They weren't boobies. They were muscles. And, the make-up was green, I was pretending to be the Hulk.
Penny: You were wearing her bra.
Leonard: That was to keep my muscles from sagging!

TBBT Quotes

Penny: Hey, Sheldon, did you change your Wi-Fi password again?
Sheldon: Yes, it's "Penny, get your own Wi-Fi." No spaces.

It's very simple. Scissors cuts paper, paper covers rock, rock crushes lizard, lizard poisons Spock, Spock smashes scissors, scissors decapitates lizard, lizard eats paper, paper disproves Spock, Spock vaporizes rock, and, as it always has, rock crushes scissors

Sheldon