Residing in Asagaya, 29-year-old Hiroto Ikuta fills his days with part-time work and conversations with neighbors. He particularly enjoys visiting Hanae Wada, a curmudgeonly but gentle elderly woman he affectionately calls "Granny." Hiroto's visits come to a sad end when she dies of a heart attack. Unexpectedly, Hiroto inherits Granny's home since she had no spouse or children. Three months later, 18-year-old Natsumi Kobayashi relocates from her hometown to study at an art school. Having no other option, she moves in with her cousin Hiroto, whom she hasn't seen in years. Despite their clashing personalities, the two start sharing a roof as they navigate their seemingly ordinary lives.