The story follows Na Byeong-soo, a young job-seeker whose life is upended when his 60-year-old stepfather commits adultery. During the ensuing parental divorce, Byeong-soo visits a hidden property owned by his stepfather and encounters Geum Chae-rin, a 29-year-old pregnant tenant. Suspecting her of being the mistress, he demands that she leaves, but she refuses, sparking a series of chaotic and emotional conflicts that redefine their understanding of family.