WARNING: The following contains spoilers for My Hero Academia #259, by Kohei Horikoshi, Caleb Cook and John Hunt, available now from Viz Media.

My Hero Academia's latest arc focuses on Tomura Shigaraki's Paranormal Liberation Front as the group plans to eradicate all of the heroes in Japan's major cities. However, that's not what people are talking about when it comes to My Hero Academia #259.

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Toward the beginning of the issue, My Hero Academia reveals the real name of Daruma Ujiko, a villain dedicated to carrying out the plans of All For One: Daruma is, in fact, Maruta Shiga, the founder of Jaku General Hospital and chairman of its board of directors. Although he's done much charity work, Shiga is responsible for creating the Nomu, who are essentially heavily modified humans. Ujiko is, unambiguously, one of the manga's villains.

As Caleb Cook, who translates the manga for Viz Media, noted on Twitter, "Maruta also means log, and was the dehumanizing term used by Imperial Japanese Unit 731 during WW2 to refer to the people they conducted human experiments on. Possibly a nod to that, given what Doc Shiga has done." Cook also added "Maruta" could mean "round + fat" and is, in fact, "Daruma" spelled backward in Japanese kana.

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Unit 731 was a division of the Imperial Japanese Army that participated in developing chemical and biological weapons around World War II. During the 1930s, Unit 731 experimented upon -- and killed -- approximately 3,000 Chinese and Korean people. As The Guardian notes, "According to historical accounts, male and female prisoners, named 'logs' by their torturers, were subjected to vivisection without anesthesia after they had been deliberately infected with diseases such as typhus and cholera. Some had limbs amputated or organs removed." The unit's actions are among the many war crimes committed during that period by the Japanese army, which continue to cause tension between the nation and its neighbors.

In response to the name appearing in the issue, many spoke out about its problematic connotations on Twitter, noting the offensiveness of naming a villain -- one who experiments on people -- after the victims of war crimes involving human experimentation.

Since My Hero Academia #259's publication, Weekly Shonen Jump -- which publishes the manga in Japan -- has released a statement saying the doctor's name will be changed. For his part, My Hero Academia creator Kohei Horikoshi has apologized to those hurt by the name choice. T ranslated by Twitter user @aitaikimochi, Horikoshi's statement reads, "Many have pointed out that the character name 'Shiga Maruta' in this week’s Jump chapter has brought up recollections of acts done in the past. I did not intend for that name to be associated as such. I take this matter very seriously and will change the name."

It's unknown whether digital issues of the manga will be changed to remove the original reference.

My Hero Academia #260 releases Feb. 9 from Viz Media.

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