"My name is Yoo Se-jin."

Lee Yeon disguises himself as a student at a prestigious university and works as a part-time tutor.
One day, he learns that the new student he will be teaching is Seo Do-young, who used to bully him at school.

"Lee Yeon, you're good at acting, aren't you?"

Seo Do-young harbors a grudge against Lee Yeon for dumping the girl he likes, and
in order to avoid studying abroad, he uses Lee Yeon's weakness to continue tutoring her. But...

"Can I solve that curiosity you mentioned?"

Do-young gradually develops a mysterious feeling about of Lee Yeon's indifferent attitude both at home and at school...