Natsume inherits his grandmother's 'Book of Friends,' which contains the names of yokai she bound. With the help of a cat spirit, Madara (Nyanko-sensei), he sets out to return the names to their respective owners, freeing the spirits.
Natsume Takashi possesses the ability to see supernatural beings called yokai. He inherits a book from his late grandmother, Reiko, known as the 'Book of Friends,' which contains the names of numerous yokai she had subjugated. Each name holds the yokai's essence, and by returning a name, Natsume can free the yokai from Reiko's control. This journey is fraught with challenges and encounters with diverse yokai, some benevolent, some malevolent. He is joined by Madara (Nyanko-sensei), a powerful but mischievous cat spirit who initially seeks to possess the Book of Friends for himself but gradually becomes a loyal companion and protector. Together, Natsume and Madara navigate the world of spirit...