Why do most men go for some very particular women?

Going anonymous to avoid conflicts. Don't get me wrong seeing the question, I'm not asking out of jealousy. However, I have a childhood friend who is extremely popular among guys. It's like they'd do anything to get her attention. As her friend, guys have often asked me to set them up with her. She gets at least 20 proposals a month and has a very high standard. She's beautiful but not the prettiest personality-wise. I've seen her reject people in extremely mean ways. With other people too her behaviour isn't good, she hurts people's deepest insecurities very easily. For example, she once publicly made fun of a classmate by referring to their family's financial condition because they wore a shabby-looking outfit. Many a times she has called other women ugly. There are bunches of girls at our class who are very beautiful or very smart or very talented and no way as mean as her. And interestingly enough, at least 90% of the guys from our class as well as from our department are ready to do anything for her. I find this to be a very curious thing. What can be the reason behind this?

Why do most men go for some very particular women?
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