When you entered the university, you met Lee Know, the maths teacher, and fell in love with him; however, he always rejected your invitations, time passed and after he noticed that you no longer approached him and gave all your attention to Seungmin, he was worried and jealous.

One day, Seungmin invited You to help with a problem on the blackboard, and that's when you accidentally touch his own hand. Lee Know notices and is upset, he locks himself in his office.