Due to an unusual ability to see strange creatures called youkai, Takashi Natsume has never fit in. Passed around from one foster home to another, he was left isolated and lonely. Over time, he has accepted that no one would ever believe him and has closed himself off to his current caretakers and classmates. When Natsume accidentally breaks an intangible barrier, he frees Madara—a mighty spirit in the form of a lucky cat. Madara notices that Natsume bears a remarkable resemblance to his late grandmother Reiko Natsume, an outcast girl who became known across the youkai world for creating the Book of Friends. It is now in Natsume's possession, along with its power to call upon the written names of the youkai Reiko had defeated. With no interest in its powers, Natsume decides to keep the book for the sake of his grandmother's memories and to protect it from scheming youkai. Therefore, he makes a deal with Madara: he will hand him the book once his time is up, and in turn, Madara will act as Natsume's unofficial bodyguard, nicknamed Nyanko-sensei. With his newfound goal of freeing those Reiko had sealed, Natsume's relationship with both youkai and humans slowly begins to improve.

Takashi Natsume, the timid youkai expert and master of the Book of Friends, continues his journey towards self-understanding and acceptance with the help of friends both new and old. His most important ally is still his gluttonous and sake-loving bodyguard, the arrogant but fiercely protective wolf spirit Madara—or Nyanko-sensei, as Madara is called when in his usual disguise of an unassuming, pudgy cat. Natsume, while briefly separated from Nyanko-sensei, is ambushed and kidnapped by a strange group of masked, monkey-like youkai, who have spirited him away to their forest as they desperately search for the Book of Friends. Realizing that his servant has been taken out from right under his nose, Nyanko-sensei enlists the help of Natsume's youkai friends and mounts a rescue operation. However, the forest of the monkey spirits holds many dangerous enemies, including the Matoba Clan, Natsume's old nemesis. Stretching from the formidable hideout of the Matoba to Natsume's own childhood home, Natsume Yuujinchou Shi is a sweeping but familiar return to a world of danger and friendship, where Natsume will finally confront the demons of his own past.

Koyama Yuzu is running an antique shop. Mayu, a cat god (nekogami), is living off Yuzu and leads an idle life playing games. Lots of other gods visit Mayu and enjoy merrymaking. (Source: ANN)

The siblings Kashou and Shigure Minazuki enjoy the company of six catgirls. Chocola and Vanilla assist Kashou in his job as a baker at the patisserie La Soleil, while the others—Coconut, Azuki, Cinnamon, and Maple—accompany Shigure in her daily life back at their home. One afternoon, when Chocola goes out for an errand, she notices a green-haired kitten alone by herself at a park and decides to bring her back to the patisserie. Soon after, the Minazuki household adopts her and gives her a name: Cacao. With a new member in their family, the members of the Minazuki household continue their everyday lives—bound to become livelier than ever.