Keiko Kinoshita resides in Suginami, Tokyo, as a member of the Kinoshita family. She is married to Keisuke Kinoshita, a salaryman, and they have a son named Keita. Due to Keisuke’s low income, the family experiences financial constraints. To supplement their earnings, they decide to rent out the second floor of their apartment. Their tenants are an elderly dog named Norayama Kuroyoshi and his grandson, Norakuro, who operate a detective agency from the rented space.