- "I am me, Tohya Hachijo. No matter how much Battler Ushiromiya's memories flow into my mind. To me, they're the memories of another person. I couldn't accept Battler Ushiromiya...."
- — Tohya Hachijo to Yukari Kotobuki
Tohya Hachijo (八城 十八 Hachijo Tōya ) is implied to be the real author of forgeries about the Rokkenjima murders, since Banquet of the Golden Witch, which were his way to cope with the memories. Together, with Ikuko Hachijo, they share the alias of "Tohya Hachijo" and "Itouikukuro".
Tohya was found on the road by Ikuko Hachijo after the Rokkenjima Incident. He was Battler Ushiromiya once, but after receiving brain damage from being hit by a car or from almost drowning, he suffered from amnesia. The accident made him unable to think of Battler's memories as his own. He began to recover his memories as Battler upon hearing of the Rokkenjima Incident from Ikuko, but develops a personality disorder; he fears that, one day, Battler's personality may seize control of him.
At one point, Tohya attempted suicide. As a result, he is forced to spend the rest of his life in a wheelchair. At the end of the Magic Ending in Twilight of the Golden Witch, it's implied that Battler finally "died" and Tohya could start living without the burden of Battler.
- Ikuko Hachijo - shared pseudonym, companion, friend
- Tohya Hachijo? - representation of
- Battler Ushiromiya - past memories, previous life
Tohya formerly had auburn spiky hair parted to the side, but now sports short white hair. He is over 180cm, well-built and wears a black suit with a white shirt and green tie. After attempting suicide, he now sits on a wheelchair.
Tohya is an amnesiac character. He does not know who he is at first, but eventually developed a sense of identity under Ikuko's care. He later on became interested in the mystery genre. When his past memories return, he became scared that Battler, his former self, would take over him, thus 'killing' him. Because of this, at one point, he tried to commit suicide. This was due to the results of the aftereffects of the damage in his brain, wherein he can't think of those memories as his own. Eventually, he began to acknowledge that he is not Battler Ushiromiya anymore, but an individual known as 'Tohya Hachijo'. But despite this, he felt that since Battler Ushiromiya was inside him, it was his responsibility to meet Ange. He was at the same time afraid that if he met Ange, he would 'die'. Because of this, he refused to meet Ange in 1998, but at the same time, regretted his actions, as he believed that if he had met her earlier, she and the Battler inside him might not have suffer for all those years. He was also apologetic towards this issue as well.
On the day of the Rokkenjima Massacre, Tohya, who at the time was still Battler Ushiromiya, escaped through the underground passage along with Eva and Beatrice. Battler and Beatrice split up from Eva and went to the submarine base while Eva escaped to Kuwadorian. Battler and Beatrice took a motor boat off the island and Beatrice attempted suicide by jumping off the boat. Battler chased after her but failed and washed up on the shores of Nijima with severe memory loss. After wandering in the mountains he passed out on the road and was found by Ikuko Hachijo, who almost ran him over with her car. For a while he forgot he was Battler Ushiromiya.
He was taken in by Ikuko who had him taken care of by a doctor. She introduced herself to him and since all he could remember was his age at the time (18), he was named Tohya, since it was written with the characters for 18, until he could remember his name. However, he would take on the name Tohya for the rest of his life. Unable to move his body at the time, for a while, he suspected Ikuko for having him under his amnesiac condition, but concludes that she isn't responsible, as her car had no damage.
As years pass, he lived together with Ikuko in her mansion in an unnamed town and his rehabilitation continued, his body began to move little by little, but he was still unable to find out who he was and as a result, suffered headaches, but as he slowly accepted that he was a new person with the new name of Tohya Hachijo, the headaches became less frequent. Eventually he stopped trying to remember his former self. Even though he was told that the frequency of the headaches may lessen through brain surgery, he declined the offer, despite Ikuko's offer of covering the costs, as he believed that it would harm his past self.
One night, he decided to read one of Ikuko's manuscript, which he finished in one night, much to Ikuko's surprise. He then gave her detailed advice on her work, to which Ikuko praised him for having the talent as a critic and a detective novel writer. When complimented about this, he seemed to remember his past self, fighting and arguing about mysteries, which excited him, but at the same time gave him a headache.
Gradually, his interests shifted from himself to Ikuko as he learned bit and bit about her during the time they have spent together. He spent his days with Ikuko debating detective novels and talking about ideas for new plots. He eventually found satisfaction with his new life with Ikuko.
At some point, Ikuko roped Tohya in her hobbies and spent writing novels together, with Tohya giving ideas and Ikuko turning them into stories with her writing skills she had built up over many years. Tohya notices that his past self had some talent for mysteries and detective novels and the like. At one point, Ikuko informed Tohya about the Rokkenjima Incident, though it wasn't until a few days later that it would cause Tohya to remember his past life.
After they had finished their masterpiece, The Strange Tale of Beatnik Island, they celebrated their success and Tohya suggested to Ikuko to have their book submitted. That night, Tohya woke up from his sleep from drinking too much wine and noticed that Ikuko was on the computer. When he asked her what she was doing and she began showing off her knowledge about the subject concerning the Rokkenjima Incident in great detail, Tohya began having a severe headache, which caused him to fall on the floor and in the process regain his former memories as he tries to call out to Ikuko for help.
- He may be connected to Black Battler, as he knew about him in Forgery no.XXX.
- In Ougon Musou Kyoku CROSS, Black Battler's alternate color scheme matches that of his clothes.
- Ryukishi07 actually planned for him and Ikuko to get married but changed the plot due to a female staff not liking the idea.
- He looks the same as young Kinzo.