She stared politely at him. "I'd love to, but now I have a boyfriend. Maybe other time."
This started a long time ago, when, she, Cassie was introduced to him, Sid, by her friend, Michelle, who was loved by Sid but was dating Tony, Sid's best friend. The purpose of all this was Sid loosing his virginity, but that didn't work out that way because he didn't know how to behave when alone with a girl. And because he loved Michelle.
Cassie is a lovely girl who is anorexic. She's quite emotive and needs affection. (Maybe that's why she doesn't eat, but this is just a supposition.)
Sid is a boy who has personality problems. His parents don't help. Having a best friend who is perfect in everything doesn't help. He feels like he's smaller than everyone around.
Anyway, even though it was no love at first sight, she quickly fell in love with him, thing which he didn't repay back. Well, not totally. He was mad about Michelle, and that was something that wouldn't stop. So, he is confused and she wants him.
She's doing everything she can to help him, in every way. But he doesn't want, or doesn't notice her. Now he is, what we girls like to call, a bastard. And Cassie is not happy about that.
She ate and tried to commit suicide. He becomes more and more confused. But always addicted to the girl he loves.
So Cassie gets over that, as Sid forgets the possibility of being with Michelle. She gets a boyfriend and she's happy about that. Very happy, indeed.
Sid looks for her to say that he's sorry. To say that he wants her back. But it seems that who doesn't repay back now is Cassie.
Revenge is sweet, don't deny it.