Our narrator's recently divorced daughter, Misaki comes back home from Tokyo to ask her parents to look after their granddaughter for the summer. Swallowing their resentment towards the sudden request, the grandparents take the child in. Sensing the loneliness behind her jubilant façade, they couldn’t help but pity the girl. Our narrator's daughter and granddaughter were supposed to reunite at the local fireworks festival. However, despite her promise, Misaki never showed up at the festival.