After gathering up his courage he finally goes over to her and asks tentatively, "Um, is this seat taken?"

She responds by yelling at the top of her lungs, "No, I won't sleep with you tonight!"

Everyone in the bar is now staring at them. Naturally, the guy is hopelessly and completely embarrassed and he slinks back to his table. After a few minutes, the woman walks over to him and apologizes.

She smiles at him and says, "I'm sorry if I embarrassed you. You see, I'm a graduate student in psychology and I'm studying how people respond to embarrassing situations."