When a female is on her period, her period blood soaks through her pants and leaves a pink, or red, mark on the seat she was sitting in.
Guy 1: So dude, did you ask her out yet?

Guy 2: Nah, i saw that she left a pink seat when she got up to turn her homework in during class, and it was a total turn-off.
by browntrousers February 21, 2009
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