Natsume is attacked by a youkai while retrieving a ball at school. In his haste to run away, he ends up breaking a youkai's seal, just like how he met Nyanko-sensei. Later that night, Natsume discovers a black lookalike of Nyanko-sensei, only to have him steal the Book Of Friends! As Natsume and Nyanko-sensei search for the black cat, they stumble across a gathering of youkai. The youkai plan to attack the humans for sealing their lord - the black cat Natsume's looking for. With Nyanko-sensei's help, Natsume gives back the lord's name and catches a glimpse of his fond and bittersweet memories of living among humans.

(Source: Wikipedia)

While fooling around in the snow, Natsume and Nyanko-sensei run into Gen, a forest guardian who lives inside a statue. Gen tries to take over Natsume's body, but instead takes over a snow rabbit that Natsume had made. Gen pleads with Natsume to help him find an evil spirit who destroyed Sui, his guardian partner, and Natsume agrees. But it seems Gen isn't telling everything he knows.

(Source: Wikipedia)

Natori invites Natsume on a hot spring trip. But noises from the closet and a kimono-clad figure dangled from the ceiling make Natsume uneasy. Not wanting to trouble Natori because of his kind gesture to enjoy the hot spring with him, Natsume investigates the hot spring himself. During the night, Natsume meets with the Youkai, where she comments that he is too soft, and attacks.

(Source: Wikipedia)

Natsume takes care of an abandoned egg from a nest, not considering it could be a Youkai. After it hatches, it turns out it is a rare baby spirit called Tatsumi, who thinks that Natsume is its parent. Natsume can't help but get attached to the little spirit even as Tatsumi grows tired and sick. But as Natsume takes care of Tatsumi, a mysterious spirit comes and wants to take away Tatsumi for his master-who wants to eat him.

(Source: Wikipedia)

Natsume encounters a spirit who was enslaved by his grandmother Reiko 50 years ago by writing his name on a torn page from the Book of Friends, and tying it to a tree in a forest. Can Natsume help locate the torn page? What was Reiko's intention of tying it to a tree?

(Source: Wikipedia)

There is a new girl in school, Taki Tooru. With her appearance at the school, circles resembling crop circles begin to appear. As Natsume tries to find out more about the circles and Taki, he is visited by another Youkai. Only this time, the Youkai isn't looking for his name, but for a snack.

(Source: Wikipedia)

Natsume is dragged off into the cave of the evil spirit that is after Taki. He temporarily loses the ability to see youkai after being poisoned by the spirit. Will he be able to stop the youkai from eating Taki without his sight?

(Source: Wikipedia)

Natsume, Kitamoto and Nishimura take a trip to an old inn to spend some time doing their homework. Surrounding the inn there is a lake in which is believed to live a mermaid.

(Source: Wikipedia)

From the day where a picture of a row of cherry trees in a desolate winter was obtained, every time Natsume wakes up, his room is covered in petals. Trying to solve the root of this activity, Natsume and Nyanko Sensei try to return the picture to Miya, a shadow figure who accompanies the picture. But why can't they return it to Miya?

(Source: Wikipedia)

Strange things start happening at Natsume's home, like Toukou's plants get destroyed, and a strange Youkai starts wandering around his house. Natsume then learns more about Reiko and her life in this town. He also learns how to get rid of the Youkai who's wandering around the house.

(Source: Wikipedia)

While out with Touko-san, Natsume spots a hurt youkai. Quickly he chases after it but as he goes to help it, it is eaten by a much bigger youkai. Natori and Hiiragi appear right after the youkai escapes and they invite Natsume to the Assembly of Conjurers. Here Natsume can not distinguish between human and youkai and is hopeful of finding people who understand him. Though this may be what Natsume has always wanted; he is too soft-heartened to realize everyone's intent.

(Source: Wikipedia)

Natsume encounters a young boy named Kai sealed in a coffin in an abandoned house. Natsume sets Kai free and finds out that Kai is being stalked by a youkai. After a time, Natsume becomes the target of this youkai and stops the youkai's stalking with Nyanko-sensei's help. In the end Natori who turns out to be the stalker and who sealed Kai in the coffin, tells Natsume that Kai is a Youkai.

(Source: Wikipedia)

Natori tells Natsume of a well near the mansion that holds a group of Oni. They are calling out to any Youkai. He also learns that Kai came down from the mountains to free the Oni. While looking for Kai, Natsume sets off one of Natori's traps in the mansion. Kai saves Natsume and heads off to kill Natori. Natsume follows him,to save Natori from getting killed. After he encounters him, he is forced to make an important decision: Which ones are more important to him? Humans or Youkai?

(Source: Wikipedia)

Natsume meets a shrine god in the form of an elderly woman. He is forced to help her return a mirror to a youkai said to bring disaster. The youkai turns out to be Reiko, Natsume's grandmother, who the shrine god only mistook as a youkai. Reiko had lent out the mirror so that the shrine god could save the life of an old tree, but the two parted after Reiko learned that the elderly woman was a youkai.

Tanuma's father leaves on a trip and a strange youkai invades his house, spreading miasma that makes all the nearby youkai suffer. Natsume tracks it down and discovers that the noxious youkai was once a resident in an all-youkai village. A portal had opened for a short time during a human ceremony that he had taken his sister to watch. However, they became trapped in the human world, and his sister died. After returning to the old temple where the ceremonies were held, the portal opens and he returns home.

It's Shigeru's birthday and Touko has asked Natsume to buy some strawberry shortcakes to celebrate. However, Shibata, an old classmate of Natsume's, finds him and asks for his help. He remembered Natsume used to say weird things, so he wanted to know if a girl he's been seeing is real or not. When Natsume meets the girl, Murasaki, she seems normal. He reassures Shibata that she is a human. Natsume later has a vision that reveals her to be a tree youkai with intention to eat Shibata. Natsume tries to warn Shibata, he refuses to listen and accuses Natsume of lying. Natsume tries to talk to Murasaki, but she does not waver. It is then revealed that although she had initially planned to eat Shibata, she fell in love with him as they spent time together, and because her tree has been cut down, she will die soon anyway. Shibata receives a note from Murasaki just in time for the two of them to spend her last moments together.

Summer has arrived for Natsume and his friends in the school. After exams, Natsume, Sasada, Nishimura and Kitamoto go on a trip to an art museum. Upon his return, Touko reminisces about an old friend that she felt she'd wronged, this makes Natsume think back to his own turbulent childhood. In the present day, a youkai living in the branches of a tree thinks back to Natsume. She had been bored because no one could see her, and when she found out that Natsume could see youkai, she often scared him to be noticed. Both of them parted ways on bad terms. The story returns to Natsume in the present day, who makes a stop at his old neighborhood to visit the youkai. The youkai, who had isolated herself from humans, is relieved to see that Natsume is okay and has found a reason to smile. The episode ends with Natsume's thoughts, "If there is somebody that you wish to meet, then you are not alone anymore."

Natsume and Tanuma take shelter under a roof from the rain. As it turns out, the house belongs to Taki, and they work together to clean her warehouse where her grandfather studied youkai. Natsume accidentally breaks a seal that Taki's grandfather made to trap a dangerous kimono youkai. The three of them race around the house to find its misplaced limbs before the youkai does--its power will be returned upon completing its body. Natsume and Taki try to get the resident youkai to help, but they refuse. When the kimono youkai comes close to hurting Natsume, they come to the rescue. After Taki thanks them, they all reminisce about their fondness for Taki's grandfather and leave elsewhere.

Natsume accidentally bumps into a woman with blood covering her body. He follows the bloody footsteps that the woman left and discovers a small house. When he opens the door, he sees badly injured youkai. There is someone killing youkai for blood, and with the help of Natori, Natsume tracks down who he believes to be the murderer: Matoba. However, Matoba captures him.

Natsume finds out who's been stealing the youkai blood: the exorcist Matoba Seiji. He investigates with the help of Natori, but is captured by Matoba's servant youkai. Matoba is willing to sacrifice any number of youkai for his own ambitions. He tells Natsume why he's gathering blood: to release the seal on a powerful youkai. Natsume learns that there are people who treat Youkai in a totally different way than he or even Natori.

Natsume is invited to go to a pottery classroom with Shigeru. It's being held in an inn where he once stayed. When he goes there, he meets an old friend: the young fox child he once saved.

Because of his poisonous arrow wound, Madara spends most of his time sleeping to heal. Without Sensei to protect him, Natsume has to remain constantly on guard. Especially since a strange stone seems to stir strange phenomena everywhere around him. To make things worse, it's the cultural festival and Natsume is appointed to serve the clients at the bazaar set by his class. But the pressure of keeping secrets from his friends is causing Natsume to break.

An event in the forest causes Tanuma to avoid Natsume the following days, which he becomes concerned about. Mirrors are mysteriously breaking around the school and one day Natsume catches Tanuma acting weirdly. It turns out that Tanuma has been possessed by a youkai looking for her mirror, which had been broken into pieces during a storm a few days before. Using him as a vessel until she reclaims her mirror, Natsume has no choice but to help her. The youkai warns that there may be others seeking the mirror.

Because of his possession, Tanuma is able to see the youkai around him and thus better understand how Natsume lives.

When a dangerous youkai from Natsume's past finds his current home, he comes down with a fever and dreams about his life right before moving in with the Fujiwaras.

Natsume spends time playing games with youkai he has befriended. He remembers games he was left out of as a child.

Natsume encounters some strange, monkey-mask wearing demons while out in a forest. They want the book of friends, and start physically threatening him until Natsume is saved by Nyanko-Sensei. Later on, Natsume encounters the demons again and is captured by them, and brought to their forest. Meanwhile, Nyanko-sensei learns some interesting things about the forest the monkey mask demons live in. Running away from the demons, Natsume and Nyanko-sensei are unintentionally saved by an exorcist - Matoba! Not wanting to confront him, Natsume runs again but gets lost in the woods, and stumbles upon a house... belonging to the Matoba. Both he and Nyanko-sensei are captured, but manages to escape and find each other, though being lost in the house. The episode ends with Matoba finding Natsume saying, "It's been a long time, Natsume Takashi-kun.

Natsume and Matoba talk, but when the conversation doesn't go the way he wants, Matoba orders Natsume to be put in a cell. Natsume escapes with the help of Nyanko-sensei. Along with his other demon companions, Natsume helps the monkey-masked demons living in the forest.

Natsume befriends a small fluffball youkai.

Yobiko, a youkai that can imitate the voices of others, sneaks into Natsumes' house and asks him to call out another youkai named Karikami. Long ago, Yobiko had been watching over a woman named Youko who was meeting with a man at a nearby shrine. One day the man stopped coming, due to an arranged marriage to another woman, so Yobiko decided to use his talent to talk to the girl. Eventually, he told her the truth about the man and ran away. When he came back to the shrine many years later, he found an old letter that had been sealed shut and wrinkled. Natsume and Yobiko later meet Karikami and after returning his name, Karikami restores the letter. Unable to read human letters, Yobiko asks Natsume to read it to him. Instead of a hateful message he was expecting, it is actually a letter of thanks for telling her the truth.

In the town Natsume used to live in, a girl recalls Natsume. She remembers his strange actions and wanted to understand him. Meanwhile, Natsume encounters a small Youkai which reminds him of the same girl and town.

Natsume is trapped in a bottle by a youkai to be offered to another named Omibashira. Nyanko-sensei transforms into Natsume and goes around his school to ask his friends about Omibashira, but gets Tanuma involved. Tanuma is attacked by one of the youkai that trapped Natsume and loses him, but as he runs through the forest looking for Natsume he finds a mansion behind the school. When Tanuma is suddenly able to see the youkai walking up the steps to the mansion, he is found out by a youkai with a bag over its head.

Natsume is saved by Tanuma and the two escape from the banquet hall with the help of Natori, who was disguised as a youkai. Tanuma is drawn more into the world of the youkai and experiences it first-hand, which greatly worries Natsume. Blood marks are found all around the mansion and Natsume's fears come true when Tanuma is attacked by Omibashira, but is protected by a stone Natori gave him. After Natsume helps Natori seal Omibashira everyone is able to escape the previously sealed exits. Promising Tanuma that he'd tell him his complaints at school the next day, Natsume finally arrives back home.

Natori is tasked with the job of finding and breaking the seal of Houzukigami, a god that was to participate in the Moon-Splitting Festival done every 10 years against Fuzukigami, another god. The festival is used by the youkai around the mountains to determine whether the harvest would be bountiful that year or not. Without Houzukigami, the match would end in a default win for Fuzukigami, causing the land to become barren. Natori tries to find the seal but is surprised to find Natsume at the festival disguised as Houzukigami, having been asked by Houzukigami's servants to stand in for their god. The match to be the winner is to catch a beast that was released from a pot.

Houzukigami's servants tell Natsume to look for the real Houzukigami while they track down the beast. Joined by Natori, Hiiragi, Nyanko-sensei, and one of the servants, they look in a building by a waterfall. The beast suddenly appears and Natsume and Hiiragi are knocked off the deck of the building. After recuperating from being dragged down the river, they try to run back to the building but are caught in a trap by Fuzukigami's servants which was meant for the beast. While unconscious, one of the servants is able to pick up a human scent from "Houzukigami", making them wonder if it's truly the god or not.

Natsume is pretending to be the god Houzukigami, so the moon splitting festival will end with a victory and the mountain will not be ruined. Winning the contest will not be easy, but with help from Natori he will find the way.

Natsume looks back at a photo of his parents, and old wounds are reopened. Natsume is having a fun day with his friends, but all of a sudden he gets a phone call. The house Natsume used to live in with his father will be sold. How will Natsume handle all of this?

Natsume, accompanied by Nyanko-sensei, set out to visit his old home. He visits a relative to pick up the key to the house, but is being followed by a youkai who wants him to draw a mouth for it. He leads the youkai away from the home of his relatives and Nyanko-sensei drives it away. When the two get back on track to finding the house, Natsume is suddenly attacked by the youkai and becomes lost in old memories.

Natsume, possessed by the youkai, thinks of an painful incident from his childhood involving the family he was living with at the time. The youkai offers to eat all his memories, so that he will no longer have to relive his pain.

Nyanko-sensei falls into a well and discovers that there is a barrier inside it, as well as Nanase, Matoba's assistant. She is looking for a certain stone with a youkai she had sealed in it, and tells Nyanko-sensei the story of how she met the youkai to pass the time.

A yokai known as "The Days Eater," turns Natsume back to a young child. Nyanko-sensei enlists the aid of Tanuma and Taki.

Natsume helps a rock washer look for his apprentice who has stopped writing him.

Natsume's old classmate Shibata (from "False Friend" / "Itsuwari no Yūjin" (偽りの友人)) calls. Natsume visit Shibata together with Tanuma, where Shibata tells them about the "Doll Mansion of Sotogi". A youkai from the mansion later attacks them.

Natsume meets Tsukiko, a daughter of an exorcist named Takuma Yousuke who has recently lost his ability to see or hear youkai. Because she lacks the ability to see youkai, she asked Natori to check around the house because she feels something is wrong and a youkai may be out to hurt her father.

Natsume and Natori discover that the youkai shiki (demon servants and friends) of Takuma Yusuke have been trying to bring misfortune into the house.

This episode shows how Natsume first befriended Nishimura and Kitamoto, along with a better look at their family lives and point of view.

Natsume is surprised when a youkai comes to seek Reiko in gratitude. Years ago, the youkai's to-be-bride received freedom from her help, and now is about to be wed. They invite Natsume to the wedding.

Natsume talks to a teenage boy at the station, who turns out to be a youkai that left a human because of their feelings for one another. The boy wants to find her because he received a wedding invitation.

After a flood occurs on Four Mask Hill during Natsume's summer school session, a mask randomly appearing in the school worries Natsume.

A competition is opened to search for a famous researcher's sealed room. The prize are his research books, and many exorcists are gathered. Natori is invited, Natsume wants to help as this might mean finding something that might let him find information about the Book of Friends.

Natsume decides to tell Natori about his secret, when the search for the seal room is over...