A chaotic human comedy about an unusual, blood-free bond. After his stepfather commits adultery, a job-seeker named Byeong-soo discovers a hidden house occupied by a pregnant 29-year-old tenant, Chae-rin. To protect his family from public ruin, they enter a secret agreement to live together. As Byeong-soo reluctantly takes over the cooking and cleaning, their endless bickering and unexpected mutual care gradually transform this dysfunctional group into a true, loving family.