Autumn 2023. Akutsu, an elderly inmate serving life in prison, is on the verge of a lonely death in his single cell. A flower, touch-me-not, that can talk like humans says to him, "What a rotten life you had." Through their "conversation," Akutsu starts reflecting on his past.

Summer 1986. Akutsu is living with Nana, a woman six years his junior, and her son Kensuke in a shabby apartment with a garden full of touch-me-nots. A one-night victorious comeback by a dying yakuza, and the story of his family recounted by a flower that blooms in prison.