During a rainy night at a library in Seoul, Y/N meets a quiet boy who shares her love for manga and anime. They spend hours talking between bookshelves, instantly connecting before parting ways without exchanging names or numbers. Y/N spends the entire summer thinking about the mysterious “library boy,” convinced she’ll never see him again. But when senior year begins in August, she’s shocked to discover he’s actually Minho—the rich, popular football player everyone at school admires… and her best friend Sarah’s boyfriend. While Minho hides a sweet, nerdy side beneath his perfect reputation, Y/N struggles with feelings she never meant to develop for the one person she shouldn’t want.