Wataru is a logical boy who loves to play video games. There is a half-finished building in his town that the residents have begun to think is haunted. One night when he goes to visit it, he meets the owner of the building (Mr. Daimatsu) and his wheelchair bound daughter who is in a vegetative state.

There is a transfer student at school (Mitsuru) who claims to have taken a picture at the Daimatsu building, but Wataru becomes obsessed with proving him wrong (because ghosts aren't logical). Whenever he approaches the boy, the boys cool demeanor unsettles Wataru and he makes a fool of himself.

Wataru enters the Daimatsu building another time, and sees Mitsuru enter the building and go through a shining door. Wataru follows, and he falls into a desert where a talking bird saves him from a pack of gimblewolves. He is returned through the portal, and told he has not been chosen as a traveller in Vision so he must not return.

Back in his room, Wataru starts to hear the voice of what he believes is a fairy. She implies vaguely that she expected him to be a Traveller. Sometime later, Wataru sees some bullies fighting Mitsuru at the Daimatsu building. He helps untie Mitsuru, who then summons a monster that devours Kenji and takes the other bullies away. Kenji returns several days later, but he has no soul.

At home, Wataru finds out his father is leaving his mother to be with another woman. This devastates both Wataru and his mom. One day, Wataru meets with his father to attempt to understand the logic of the situation, but the meeting leaves him more upset. In the night, Wataru is woken by Mitsuru, who has come from Vision to save Wataru. His mother left the gas on to kill herself. Wataru turns off the gas, calls the police, and then leaves for Vision.

In Vision he meets Wayfinder Lau who gives him a challenge. In the challenge, Wataru is declared a brave, and given the brave sword. Wayfinder Lau explains he must find 5 gemstones to make the sword into Demon's Bane. Then, he can go to the Tower of Destiny, meet with the Goddess, and ask her to change his destiny back home so his father never leaves their family. Mitsuru is there already, making his way to the Tower, and so Wataru must attempt to catch up with him if he is to succeed. They cannot work together.

Soon after leaving the Wayfinder's village, Wataru meets Kee Keema, a waterkin (giant lizard man). Upon learning he is a Traveller, Kee Keema asks if he can join Wataru, since Traveller's are thought to be good luck, and Wataru agrees. They make their way to a village, where Kee Keema leaves Wataru, explaining he has to go tell his village chief that he will be helping Wataru on his journey.

The next morning, Wataru is awoken by the inn keeper and a Highlander (local law enforcement) who arrests him for murder. He is covered in blood, and the person next door was dead. There have been a string of murders, and Wataru is accused of them all.

While being interrogated by Kutz, he reveals he is a traveller. That night, another murder occurs and Wataru is freed. He discovers the real murders are some kids who were using a kitkin (cat girl) who they had blackmailed. Wataru sets the kids up, and rescues Meena who agrees to join Kee Keema and help Wataru on his journey. Wataru is made an official Highlander for solving the murder case.

Wataru sneaks off in the night to go visit an abandoned church that is rumored to have treasure in it. Underneath the structure, he gets attacked by a monster, only to be saved by Kutz, Meena and Kee Keema. He gets a gemstone.

Wataru is captured by worshipers of the old god in a racist town. He is rescued by Misturu and cast into the Swamp of Grief, alone. There he rescues a dragon, but his hateful spirit murders someone who looks like his dad. He passes out and is rescued by a scholar who tells him about the Blood Star - a sign that one traveller and one resident of vision will be chosen as the thousand year sacrifice.

He is reunited with Kee Keema and Meena. Wataru rescues a young scholar and gets a gemstone. He then returns to the racist town where he fights the lead worshipper of the old god, rescues a craftsmen, and gets the third gemstone. The craftsmen makes a dragon flute from the scale and Wataru calls on Jozo. Jozo takes Wataru to the highlands where discovers a cursed village of Travellers who did not complete their mission. They are cursed because one took something from the real world to give to the country of the North. Wataru is asked to return the documents (plans for a steam engine).

Jozo flies him north, where they catch up with Mitsuru, who is after his last gemstone. Unfortunately, it protects Vision from demons. Mitsuru destroys the capital, steals the gemstone, and ascends to the tower of Destiny. Demonkin are released, and everyone must fight to survive. Wataru find his 4th gem in the rubble of the capital. Kutz is killed.

Wataru ascends to the Tower (thanks to Wayfinder Lau) where he finds and rescues the soul of Kaori Daimatsu (the girl from the beginning) and Kenji (the bully). He confronts his hateful spirit, and accepts it, but Mitsuru fails to, and he is killed. Wataru takes the final gemstone from him. He then fights the demon lord, who had been speaking to him as a girl throughout the book. He defeats her. He asks the Goddess to destroy the demonkin and save all of vision because he learned that simply changing his destiny in the real world won't help anything. She does as he asks.

Wataru returns to the real world just where he left and rescues his mother from the gas. No one knew he was gone, but they all remark how much he appears to have changed. At the very end, he meets the perfectly healthy Kaori Daimatsu at the Daimatsu tower, which is finally being completed.