Alcohol, cigarettes, men.

Ha-Yoon, a 20-year-old repeat student who had been living her life with all the bad things, meets her homeroom teacher, Hyung-Won! Ha-Yoon feels curious about him who doesn't care about the rumors others gossip about and always breaks expectations, and for the first time, she learns of love.

"I like that teacher."

"That's not love. You have a lot of delusions at your age."

But unlike other men who would fall for you if you teased them a little, he's the world's most stubborn man, so it's not easy... But it's okay, because I'll break down all those stubborn walls!

(Source: Ridibooks, translated)