Natsume Takashi has the ability to see spirits, which he has long kept secret. However, once he inherits a strange book that belonged to his deceased grandmother, Reiko, he discovers the reason why spirits surround him. Containing the names of these spirits, a binding contract was formed between the spirits and the owner of the book. Now, Natsume is determined to free the spirits and dissolve the contracts. With the help of a spirit cat, his days are filled trying to return the names to these spirits.
Since he was young, a teenage boy named Natsume Takashi has been able to see youkai, but keeping this ability a secret has now become a heavy burden for him and has made his life difficult.
This begins to change when Takashi inherits his grandmother’s “Book of Friends.” He discovers that she, Natsume Reiko, shared the same ability as him and starts to understand why he was always targeted by both good and bad youkai.
After learning the true meaning behind the Book of Friends, which allows him to manipulate the spirits listed within its pages, Natsume undertakes a journey with his bodyguard, the infamous spirit Madara, to free the spirits of their contracts with Reiko.
Natsume is lonely; he has an ability that separates him from others: he can see and interact with spirits. Soon, however, Natsume discovers that he’s not alone: his grandmother Reiko also had the gift. But things get hectic and possibly dangerous for Natsume when he finds out that he also inherited the ‘Book of Friends’, a book that contains the names of all the spirits Reiko defeated and subjugated. He finds himself hounded by his grandmother’s underlings and, with the help of a ‘cat’ charm spirit, decides to free them from the Book’s shackles, as well as protect the book from those who seek to misuse its power…