Sunghoon as your Professor, You have a feelings for him and he knows it because you confessed to him a long time ago but he rejects you because he is engaged but you didn't stop liking him

While you a troublemaker student who is always in guidance but you are not expelled from school because your parents have a strong attachment to your school

"You should be thankful because you were not sent to the guidance today"

He said while leaning on his chair and looking at you coldly