OVA
Description
Madara, commonly called Nyanko-sensei, is a powerful yokai and one of the central figures in the anime Natsume's Book of Friends: The Stump of the Suzunaru Tree. His original form is that of a large white wolf-like beast with the ability to fly, and he ranks among the higher class of yokai, known by name throughout the spirit world. For a long time he was sealed inside a maneki-neko, a beckoning-cat figurine, which had been placed at a shrine. Takashi Natsume accidentally released him from this seal, and although Madara can return to his true form at any time, he has become so accustomed to the cat vessel that he spends nearly all his time in the shape of a round, plump cat. Because the figurine serves as his physical vessel, ordinary humans can see him, which is unusual for a yokai.

In his everyday cat form, Nyanko-sensei is loud, proud, quick-tempered, and deeply self-indulgent. He has a strong appetite and is especially fond of sake, sweet snacks such as manju and dango, fried tofu, shrimp, and other treats, and he often complains or tries to trick others into giving him what he wants. He regularly boasts that he is noble and great, but he also has a playful and immature side, sometimes playing with cat toys even while insisting that he is not a cat. Below this comedic surface, he is an ancient and experienced spirit who is pragmatic, sharp-witted, and honest about the dangers that Natsume faces in the supernatural world.

His stated reason for staying with Natsume is a contract: he serves as Natsume's self-proclaimed bodyguard, and in exchange he will inherit the Book of Friends after Natsume dies. Because the book contains the names of many yokai, possessing it would give its owner considerable power over them. In the early part of the story, he is suspicious that Natsume might use the book to control other spirits, and he treats their arrangement mainly as a practical deal. Over time, however, the relationship moves beyond simple self-interest. Although he would never admit it, he grows genuinely attached to Natsume and becomes protective of him in a way that goes far beyond the original agreement.

Within the story, Nyanko-sensei serves as Natsume's constant companion and guardian. He accompanies the boy through encounters with other yokai, explains the rules and customs of the spirit world, occasionally teaches him spells, and defends him against hostile creatures and exorcists. In The Stump of the Suzunaru Tree, he is present when Natsume meets an elderly yokai who is the spirit of a tree stump. The old spirit asks for help returning to his home and remembering a promise he made to a human long ago before he disappears into the spirit world. Nyanko-sensei stays close to Natsume throughout this encounter, offering his usual mix of grumbling commentary and practical assistance.

His relationships are shaped by his long life and his connection to the Natsume family. With Takashi Natsume, he has a bickering partnership that gradually develops into a deep bond of trust and affection, with the two often arguing while remaining inseparable. With the Fujiwara family, Natsume's guardians, he lives in their home and is treated as a pet cat. He also has a past connection to Reiko Natsume, Takashi's grandmother. She repeatedly challenged him to contests, and he refused, which is why his name is not recorded in the Book of Friends. He remembers her as a lonely person who was always alone, and this history gives his relationship with her grandson an added layer of meaning. Among other yokai, he is regarded as a formidable senior figure, and he sometimes drinks and socializes with local spirits. He has a strained relationship with the exorcist Natori Shuuichi, and he is familiar with Natsume's friends Tanuma and Taki, remaining friendly with them even though he is wary of Taki's habit of clinging to him.

His notable abilities come from his nature as a powerful yokai. In his true form, he becomes a large white beast that can fly and can release light that repels or drives away other yokai. This form is strong enough to overwhelm ordinary spirits and even trained exorcists. In his cat form, he retains some degree of supernatural power and can, for example, use lightning to discipline minor troublemaking yokai. He can also transform into human appearances and has been shown taking the shapes of both Takashi Natsume and Reiko Natsume. His most distinctive trait is the contrast between his harmless-looking cat body and the immense power and long experience that lie behind it, a contrast that defines both his comedic role and his importance as a protector throughout the story.