Takashi Natsume sees Yokai. When he was a child, after his parents died, it caused him lost of trouble when he told the relatives who took him in what he saw, so he has learned to hide it. But his grandmother, Reiko m also had the same ability, and was rejected all her life by people. Instead, she turned to Yokai for someone to interact with, playing games with them and if they lost, making them write their names in her notebook.
Natsume is often bothered by spirits who think he is Reiko. Some of them attack him, while others only want their names out of the book. He can return the name to them by imagining the name in his mind, putting the page in his mouth, and breathing out, but doing so takes all his energy. Returning their name frees them to move on, but since not all the spirits like him, he has another spirit, Madara, who he calls "Nyanko Sensei" to be his bodyguard and protect him. He calls him "Nyanko Sensei" because he is bound into a Maneki- Neko or "Beckoning/Lucky Cat" statue. When he takes on statue form, everyone can see him, but they think he is just a cat. In his true form, only Natsume can see him.
In this book, Natsume is asked to join a summer group that is going to do a walkthrough in a haunted house. They need 50 people to participate, and he's the last person they need to get permission. He goes along, but the House is haunted by Yokai, and the yokai begins abducting members of the group as they go through the house. However, it turns out that the president of the group once encountered the Yokai in the house when it helped her find a special amulet she lost there. She's done this activity to try to meet it once more and thank it for helping her. But the spirit doesn't want to meet her. It considers itself tainted. Can Natsume speak to the Yokai and convince it that it isn't tainted, and get it to free all the people it has abducted?
Later, when Natsume frees a frog from a spiderweb, he is marked by a Yokai who wants to eat him. Through the assistance of the Yokai whose messenger he freed, he discovers that the mark is a five day mark- the Yokai will drain his energy for five days or until it has enough energy to leave where it is. Hinoe, a Yokai who once knew Reiko, helps Natsume for her sake. But when the spirit sends its shadow to find Natsume and eat him, can he stay out of its way for the whole five days?
Next, Natsumi discovers an actor, Shuichi Natori, has the same ability to see spirits, and a birthmark shaped like a lizard that moves around his body. But while Natsumi wants to be a nicer person, both to other humans and Yokai, Natori uses his own powers to exorcise and kill Yokai, while having three Yokai who serve him. But when he comes to destroy a Yokai he once helped, can Natsume protect the Yokai from Natori? Can the two of them ever agree on Yokai and whose attitude will affect whom when it comes to Yokai?
Later, Natsumi is at school when he encounters another Yokai who travels in a flying umbrella. When the Yokai senses that Natsume can see him, he demands that Natsume let him have his body. Nyanko comes along to prevent it, but he learns that the Yokai is carrying the spirit of a harpist named Asagi. Asagi was a lutenist beloved by the gods, until she fell ill. She went away into the forest, and her skin sloughed off. Now, she wishes to play for the gods one last time, but she needs a body to do so. And then the Yokai puts Asagi's spirit in Natsume as he sleeps. Natsume agrees to help Asagi, but can they find the things needed to make a lute, and return to Asagi's beloved Lord Mibu in time to help her put on one last concert for her friend?
This second book, much like the first, really touched my heart. We see more of the Yokai world, and how Yokai form attachments just like humans. But being unaging, if they form attachments with humans, it often leads to grief on both sides since humans age and die, unlike Yokai, and also unlike Yokai, are often weaker and more fragile, leading the Yokai to inadvertently damage their human friends without meaning to.
Also, since humans die, it means that the Yokai is driven to grief or rage when the human they counted as their friend is no longer there for them. But even while friendship between the two is a bad idea in most cases, it can also be beautiful and change both human and Yokai lives for the better. It's this beauty that Natsume's Book of Friends explores. While Natsume's grandmother, Reiko, had it wrong, Natsume can still make bad decisions, but for the most part he does the friendship aspect right.
And it's this reason that makes me want to read more of these stories and keep seeing more. Nyanko may view Natsume as an annoyance, but I think his friendship with Natsume will change him for the better, and Natsume as well. It's this peculiar relationship that makes the glue in this story, but it's a compelling one, along with all the other stories of Yokai. Highly recommended.