Bitterness. Cold. Hotheaded. Are all things that Kim Minji, the young CEO, is familiar with. She's rich and successful, and very smart in managing the company so it remains the top in South Korea. But none of her employees want to get along with her because they don't want to become victims of her temper. When a young woman, Pham Hanni, is assigned to be her secretary, she soon realizes that she is entering hell and dealing with the devil herself. No matter how excellent Hanni's work is, Minji will always hate her. But Hanni slowly falls in love with the devil, and things become more complicated than ever.

Haerin was a big nerd, but she is not a wimp. Her sharp mouth and guts always made her get into trouble with her bullies. Danielle is the President of the Student Disciplinary Committee. Although she has the face of an angel, she becomes a devil when she deals with troublemakers. One incident leads to another and they suddenly have to live together. Minji, a famous womanizer on campus, a Don Juan in female form. But when she meets Hanni, her life goes up and down, she wants that girl, so bad. An ordinary love story.