Tsugumi Douzono, who works for a major electronics company in Tokyo, is spending a long holiday at her grandmother's house in the countryside. After her grandmother passes away, Tsugumi decides to live in the house and work remotely from there. The following morning, an unknown man in his 50s arrives at the house. It appears that the man was her grandmother's student and has been given a key to the property. Although Tsugumi does not fully understand the relationship between her grandmother and the man, he moves in to become her roommate.