Over the past weekend, details emerged of a serious scandal that is rocking the manga world, leading to major authors removing their works from Manga One, the digital reading app of publisher Shogakukan. It has been revealed that the publishing house, one of the biggest in Japan, rehired an author who had been arrested in 2020 for sexual assault of an underage girl under a false name to work on a new manga.
Shoichi Yamamoto, the author of Dakuten Sakusen, was arrested in 2020 for submitting a high-school girl to repeated sexual abuse over the course of years while Yamamoto was teaching art part-time at the girl’s school. In February 2026, he was convicted and ordered to pay 11 million yen ($71,000) in damages to the victim. Shogakukan canceled Dakuten Sakusen after his arrest in 2020, citing “health reasons” on Yamamoto’s part.
In 2022, Yamamoto was hired again, under the name Hajime Ichiro, by Shogakukan to work as a writer on a new manga, Jojin Kamen, illustrated by Eri Tsuruyoshi. According to reporting by Japanese newspaper Mainichi Shimbun, editors at Manga One knew of Yamamoto’s conviction when he was rehired, and even got involved in out-of-court settlement talks between him and the victim that would have required the victim to keep the abuse secret. The two sides failed to reach a settlement, which led to the recent conviction.
On Feb. 27, Manga One released a statement and apology, which were widely criticized for not providing enough information on how or why Yamamoto had been hired again. On Feb. 28, Shogakukan shared another, more detailed statement, and also announced that distribution of Jojin Kamen would be halted.
After the news emerged, several manga authors spoke up publicly to criticize Shogakukan, including One, the author of One-Punch Man and Mob Psycho 100, the latter of which was published by Shogakukan. Many authors who have their works available on the Manga One app decided to have them removed, including Rumiko Takahashi (Ranma 1/2, Inuyasha), Kanehito Yamada (Frieren: Beyond Journey’s End), and Ryuhei Tamura (Cosmos).
This isn’t the first time that the manga world has been rocked by a sexual abuse scandal involving underage victims. In 2017, Nobuhiro Watsuki, author of Rurouni Kenshin, was charged and fined for possession of child pornography. Notably, his ongoing manga Rurouni Kenshin: The Hokkaido Arc resumed publication shortly after the scandal. High-profile colleagues of Watsuki never condemned his actions, to the point that Takehiko Inoue, Masashi Kishimoto, Eiichiro Oda, and many others contributed with original illustrations to a Kenshin 30th anniversary exhibition in 2024.
Response to the Yamamoto scandal has been much more vocal. However, some prominent artists working for Shogakukan, such as Gosho Aoyama (Detective Conan), have yet to comment. For the moment, it seems that criticism is being focused on Manga One and its editorial staff. According to the second statement, the publisher recognizes this “as a grave incident for which the company bears management oversight responsibility, reflecting a lack of awareness regarding human rights and compliance.” Shogakukan also vows to establish an investigative committee “to clarify the facts and causes, including the circumstances surrounding the start of serialization and the editor’s involvement, including any settlement discussions. Following that, we will issue a report on the investigation findings, impose strict disciplinary actions, and formulate and implement measures to prevent recurrence.”
Update: After the publication of this article, new details have emerged concerning Shogakukan hiring another convicted mangaka under a false name. Tatsuya Matsuki (author of Act Age, published on Shueisha’s Weekly Shonen Jump) was found guilty in 2020 of committing indecent acts with a middle school girl. Matsuki was then hired in 2024 by Shogakukan under the name Yatsunami Miki to work on the manga The Counselor through the Years and Stars. In this case, the editorial staff of Manga One and the manga’s artist, Yukihira Kaoru, were fully aware of Tatsuya’s identity. Shogakukan decided to make these details public in the wake of the recent scandal.
