This occurs when you get a chick in a room alone. Make-out with her/get her really horn. Turn her around so she faces a bed, bend her over, and rip her pants down. She is expecting you to "give it to her" hard. Simply spit in her butt-crack and walk out the door, leaving her very horny and probably pissed.
Dude, I finally gave a random girl the spit-teaser last night. Boy, was she mad!