The new guy at school has certainly made a great first impression. He has girls swooning at his feet because of his good looks and has the respect of all the guys because of how he treats them and speaks to them like adults instead of young children. Yep. Just about everyone has fallen for Kim Joonmyeon. 

Well everyone except exchange student Zhang Yixing 

He think's Joonmyeon's just average and like any other person he's ever met. His friends say he thinks that for now but will end up falling for him one day. But you see, even if Yixing was to fall for Joonmyeon, just like every other student in the school, nothing can happen between them.

Joonmyeon's the newest Science teacher and relationships between teachers and students are strictly forbidden... but rules are made to be broken... right?