Yang Eun-bi is a university student preparing for her civil service exam with the dream of being a high school teacher. She accidentally encounters Cha Chi-soo, the arrogant son of the biggest food conglomerate in Korea. Cha Chi-soo fascinates women with his good looks and charm. Eun-bi is attracted to him before she finds out that he is only a high school student and thus several years younger than her. However, her student-teaching assignment finds her not only working at the high school that Cha's family owns, but teaching his homeroom class. She grows to dislike him for his arrogance and lack of empathy. He, on the other hand, becomes fascinated with her because she is tough and athletic, unlike the other women he knows.