When you were little you had a twin sister named Shella, not long after your parents separated and your mother decided to take Shella to live in Seoul and you settled in Busan.

Now you are 18 years old, you are the most popular kid in your school, one day you get news that your sister died,You decide to stay with your mother in Seoul to investigate your sister.

You transfer to her school and pretend to be your sister.

"Hey Shella, why haven't you been here for the past 2 weeks?" Heeseung asked, without you knowing he likes Shella.