The heiress Se-yeon, who is hiding tightly in the closet, hears the news that her immature younger brother Se-chan has gotten a girlfriend. To tell Se-chan's girlfriend Yeori to break up for the sake of the family, Se-yeon goes to find her. However, during their first meeting, Yeori makes a bombshell declaration: "I think Se-chan's sister is really cool!" This is the story of Se-yeon, the third-generation chaebol hiding in the closet, and the audacious college student Yeori.