The most popular boy in school is notorious for being a player—he dates a girl for a few weeks and sleeps with them, and then he moves on and on and on, never running out of girls willing to be with him. And then the new girl arrives.
She's never been particularly impressed by pretty boys, and that's why she doesn't do what he wants. She doesn't run to him to slobber all over his face. There is, in fact, a good reason for this. The reason is, she's far more interested in his twin sister, labeled a "freak" but still beautiful.
She knows her twin; she knows he prides himself on being able to conquest any girl he sets eyes on, and that's why she tries to discourage the new girl's attentions... but she can't help but be intrigued, and she has to navigate the minefield of her brother's interests and her own.