Before starting his job in Tokyo, Koji takes a trip to the hot springs with his mother Reo. Reo's husband declines the family vacation, saying he is too busy with work. In reality, her husband is having an affair, and this fact troubles Reo alone. Seeing his mother's depressed expression, Koji gradually starts to see her as a woman. Torn between familial bonds and romantic feelings, Koji pursues Reo.
