Oh Sehun has a perfectly great school life, thank you very much. Well, that is, until a problem-child enters his class and messes up his until now good life. And to make matters worse - the said problem-child and he was supposed to be friends when they were younger. This does not amuse Sehun a bit, but sadly his classmates, EXO, finds this extremely hillarious. And because of various reasons (mainly his classmates) Sehun and the others gets tangled in all kinds of weird situations. He's perfect, she's not. Oh Sehun is the perfect heir. Yoo Ji-Min is everything but that. He has flawless grades, is polite, goodlooking and nice. She is smart, but a rebel and an oncoming storm. He knows his place, and always thinks of others first. She is mostly heartless. So when Ji-Min is admitted to the Advanced class Sehun and the other boys from EXO is attending, things are sure to get messy.

Lee Jieun, the daughter of a wealthy family, had a secret she couldn't share with others. Superpowers? No. But something else that set her life into a completely different course. Her parents knew it, naturally, and maybe a few family friends. But no one else did, and they weren't even supposed to know. And all she could ever do was to fret how she would ruin her parents' plans and never be the heir they truly deserved. Kim Myungsoo on the other hand was a bit different. Being like Jieun, coming from a wealthy family, he didn't really care about his status and he rarely used it to gain something. He had his own plans, his own future with clear steps. But his parents liking Jieun's parents caused his life to take a U-turn, a turn he might have not wanted at all. And to add more misery, Jieun loved Myungsoo with her whole heart, but not even once had she dared to confess, nor even tried to make it clear for him. Myungsoo surely loved someone as well, but not necessarily Jieun. And what if neither of them could avoid the arranged marriage? Could they truly have a happy ending in this story?

Before Laddie's only wish is to confess to her crush before she moves to U.S. Even if she was rejected or accepted she wanted to get her feelings off her chest. She had planned her confession beforehand, but things didn't go the way she wanted. Instead of confessing to her crush she confessed to her crush's best friend, Sehun. Now a high schooler, Laddie wishes to forget the confession that went wrong, but...