22-year old Kawano Ayu was brought up way out in the country. She's a rough-mannered tomboy. When she meets Tetsu, a divorced beautician, the two fall in love and get married. Immediately after their happy new life begins, they are visited by a 5-year old boy, Yuki, who claims to be Tetsu's son. Ayu reluctantly becomes the boy's mother, but has no idea how to raise a child. What's more, at kindergarten, she must confront the elegant mothers of the neighborhood. Ayu's humorous life as a rookie mother begins.