Howard: She hid my XBOX like I'm a child. And my mom got me that for my birthday so if you don't give it back, I'm telling.

Bernadette: If you like pushing buttons so much, try pushing them on the washing machine.

Howard: A micro-valentine for a microbiologist.
Leonard: From her micro-husband.

Bernadette: Sorry doesn't clean my underpants, buddy.

Sheldon: Okay, stop ruining Valentine's day and order my pizza.

Sheldon: I believe the painful sensation felt after passing a meal of spicy chillies is proof that the rectum does possess the sense of taste.

Raj: The theme will be that the greatest love a man can have is the love he has with himself.
Stuart: That's good. Or maybe something a little less hand in the pants.

Alex: Well, I know she loves playing the harp, so I found this beautiful music box that plays one of her favorite songs.
Sheldon: Now, Amy already has a real harp and it can play any song. What are you trying to pull here?

Alex: I know she's a fan of The Canterbury Tales. So I found this cool map that illustrates the characters' journey through England. I thought we could put it in a really nice frame.
Sheldon: But she's got Google Maps on her phone.
Alex: I don't know how to respond to that.

Raj: It's nice that all the people who are lonely on Valentine's Day can come here tonight and be together.
Stuart: Yeah, I'm really looking forward to it. In fact, there's no place I would rather be than here.
Raj: Except on a date with anybody.
Stuart: Literally anybody.

Amy: As you know, I had planned a traditional evening of romance and gifts.
Sheldon: Yes, and as you know, I planned to pretend to enjoy it. I've been working on this facial expression all day.
Amy: And I appreciate your effort, but upon contemplation, I decided I was being selfish. So, I canceled our dinner reservations and came up with an even better way to celebrate Valentine's Day.
Sheldon: What is that?
Amy: By doing none of it. No dinner, no romance, no gifts. We stay here, order a pizza and watch one of your beloved Star War Trek things.

Sheldon: This is the most thoughtful gift that anyone's ever given me. And that's including an amazing gift that I gave myself earlier today.

Raj: Later, losers!

Penny: Leonard Hofstadler...
Leonard: Yes?
Penny: Will you be my valentine?
Leonard: Sorry. Maybe next year. I'm just kidding! Romance ninja. Let's have sex.

Leonard: I'm cool with surprises, but nothing on the Jumbotron. I don't want to cry on the big screen like that.