Like-minded people.Her mother-in-law, Reiko, and her daughter-in-law, Serina, have not been compatible for a long time, and they repeatedly clash at every opportunity.One summer, several years have passed since the two stopped seeing each other.The story begins when Serina visits Reiko's house to borrow a "registered seal" in order to integrate part of Reiko's furniture store into their own furniture store.Reiko welcomes Serina to her husband's birthplace for the first time in several years, as usual.For Serina, the longest and unforgettable summer of her life has begun.