Natsume, who lives a busy life between humans and monsters, accidentally reunites with his former classmate Yuki, and recalls the bitter memory of being haunted by monsters. At this time, Natsume met the woman Tsumura Yoriie who appeared in the memory of the monster whose name was returned. She, who met Reiko, now lives a stable life with her only son Mukuo. Natsume's state of mind has become peaceful through communication with them. However, the town where the mother and son live seems to be lurking with mysterious monsters. After returning from investigating this matter, the "demon seed" parasitic on the body of the cat teacher grew into a tree and bore fruit overnight in the courtyard of the Fujiwara family. And the cat teacher who ate the fruit similar to his own shape actually split into 3——! ?