ONE, creator of ONE PUNCH MAN and Mob Psycho 100, along with many other manga authors have condemned Shogakukan’s online platform, Manga ONE, in relation to the scandal surrounding Shoichi Yamamoto. Yamamoto was charged and fined for sexually assaulting a 15-year-old student in 2020, but returned to work at Shogakukan under the name “Hajime Ichiro” in 2022.
On February 27th, 2026, Manga ONE’s editorial department released an explanation and apology in regards to Shoichi Yamamoto. In the statement, the company explained that it should not have hired Yamamato, who was the writer of the Jojin Kamen manga using the pen name “Hajime Ichiro.” Shogakukan halted digital distribution as well as shipments of the printed volumes of the manga.
Originally, Yamamoto was arrested, indicted, and fined in 2020, and the company suspended the serialization of his manga, Daten Sakusen. According to Japan Times, Ichiro was allegedly ordered by the Sapporo District Court on February 20, 2026 “to pay ¥11 million in damages to the victim of his sexual assault” from his arrest six years ago. The outlet claims his abuse was towards his student while he taught at a private school in Hokkaido. He was then “indicted and fined for violating the child prostitution and child pornography prohibition law.”
Kyodo News reports “Shogakukan Inc. allowed an author to produce works under a different name despite knowing he was convicted of a sex crime.” Although verified details on the court case isn’t publicly available online, the news report alleges this convicted author is Shoichi Yamamoto. Anger ignited on social media, prompting early English and Japanese explanations on the matter to include a mix of misinformation and leaps in logic as the public attempted to make sense of the back-to-back news.
In response to the backlash, Japanese publisher Shogakukan released a statement on how it will be conducting an internal investigation of the situation. It will establish a third-party committee to understand Manga ONE’s editorial department hiring process, as well as the circumstances around the editor who was involved in the out-of-court settlement. This editor was also in charge of “the negotiations between the original author and the victim,” and even “proposed notarizing the terms being negotiated.” Manga ONE’s editorial department and Shogakukan apologized to readers, other authors within its organization, as well as Jojin Kamen‘s artist, Eri Tsuruyoshi.
Tsuruyoshi posted their statement on the matter, expressing their shock. They stated they had only met Yamamoto once as all other communication was facilitated through a third party named “Narita.” The artist had no knowledge of Yamamoto’s crimes and hopes the victim can recover.
Many manga authors, whose works are distributed on Manga ONE, took to their X accounts to voice their disappoinment and anger. Ryuhei Tamura, posted on X to share he told his editor to stop serialization of COSMOS on the platform. Others, including Ai Minase (Hachimitsu ni Hatsukoi), Minoru Takeyoshi (Shokubutsu Byorigaku wa Asu no Kimi o Negau), and Miko Mitsuki (Momo Lover) expressed their personal decision to remove or halt their works on the platform as well.
Although works from Rumiko Takahashi (Ranma 1/2) and Kanehito Yamada (Frieren) have been “discontinued” on Manga ONE, both authors have not publicly commented on the reason why. It’s possible this was a contractual issue, but without an official statement from the party’s or even Manga ONE, any reasoning is pure speculation.
In an attempt to provide transparency on how it intends to conduct its investigation, Shogakukan revealed and explained how it hired act-age creator Tatsuya Matsuki even after he was found guilty of assault on a female middle school student in 2020. The details for the act-age case was released with the consent of the manga author. During this investigation, Shogakukan unearthed enough information to disclosed that the Manga ONE editorial department would also need to conduct its own investigation on hiring system as it knowingly hired yet another author with an alleged criminal past.
Again, public anger erupted over Shogakukan’s statement as it revealed the Manga ONE editorial department suggested a pen name for Matsuki to obfuscate his past. He used the pen name, Miki Yatsunami, which was “made based on the judgment of Yatsunami and the editorial staff.” Both Manga ONE’s editorial staff, as well as act-age‘s artist, Kaoru Yukihira, knew Matsuki’s circumstances and identity.
In fact, Manga ONE staff reached out to the convicted writer through X (formerly Twitter) on August 29, 2024 to request a meeting. Despite being aware of Matsuki’s alleged crime, the editorial team decided to hire him under his pseudonym in order to publish Seiso no Shinrishi on the digital platform. Shogakukan will temporarily stop updates for the manga beginning Monday.
Source: Mainichi JP, Nifty News
