Nayeon could be easily described as perfect. She has a great family, awesome friends, a secured future, beautiful looks, and above all, she was beyond happy. But her life suddenly takes a rough turn when she's paired up with the infamous and feared Yoo Jeongyeon for a project. Her concept of 'perfection' changes drastically because of this bad girl. Intrigued by her, Nayeon will try her best to unmask the real Jeongyeon that's hiding underneath that cold, heartless and full of pain shell she created to isolate herself from everyone. And she's determined to fix Jeongyeon.