Amy: I must say, Penny, this is great fun.
Penny: Glad you're enjoying yourself.
Amy: Until I met you and Bernadette, my trips to the bathroom had been entirely focused on elimination. Now they have a delightful social aspect.
Bernadette: Amy, you must've been in the bathroom with other women before.
Amy: Of course I have. But they were strangers and seemed off-put when I engaged in friendly stall-to-stall chit chat.
Bernadette: Some women don't like to get chummy when their panties are down.

Howard: I'm sorry I didn't take you to the airport. I just want you to know I'll never forgive myself for being so selfish. And I promise to keep you close for the rest of my life.
Bernadette: Oh, no, that thing's gonna end up in my bedroom.

Bernadette: (Shouting from the bathroom) How many times do I have to tell you to replace the toilet paper when it's empty?
Howard: I'm in the middle of something.
Bernadette: So am I!

Bernadette: Gosh, Amy. I'm sensing a little hostility. Is it maybe because like Sheldon's work, your sex life is also theoretical?

Raj: She didn't even get to see my penis.

Sheldon: There's no need to interact with me. I'm just here to observe.

Penny: I'm sorry, shoes, but you have to go back.
Shoebox (Penny): But, Penny, we love you.
Penny: I love you, too, but you cost more than my rent.
Shoebox (Penny): But Penny, you look so good in us.
Penny: (To Amy) Damn it, the shoes are right!