You know exactly what you'd do. You'd say hi to him, and when he left you'd cut him all up so your friends wouldn't think you really liked him.
9 seconds sound clip from the The Breakfast Club movie soundboard.
You can hear this line at 01:20:52 in the Blu-ray version of the movie.
Quote context
[...]
- With all of us or just John?
- That's a real nice attitude, Claire.
- Oh, be honest. If Brian came walking up to you in the hall on Monday, what would you do?
- I mean, picture this. You're there with all the sports.
- No way.
- Okay. What if I came up to you?
- Why, 'cause I'm telling the truth? That makes me a bitch?
- No, you know how shitty that is to do to someone.
[...]