Yoo Jae-gun, head of an infamous gangster organisation, becomes troubled by the future prospects of his only daughter, Eun-byul, who refuses to study. Then coincidence or fate brings together Eun-byul and goofy-looking high school teacher Jang Yi-san in a somewhat sticky situation. After finding out that Yi-san can actually inspire his troublesome daughter to focus on her studies, Jae-gon offers a deal to Yi-san: become his daughter's private tutor in exchange for one million won. The catch is Yi-san has to move in with her. And the money? It's given as security for his own life.