On 12 October, 2012 a plastic container was left on the second floor in the gymnasium of Tokyo’s Jochi University (aka Sophia University), one of Japan’s most prestigious schools and alma mater of Tadatoshi Fujimaki the writer of the hit manga series Kuroko’s Basketball (aka The Basketball Which Kuroko Plays).
Inside the container was a liquid capable of releasing poisonous hydrogen sulphide. Attached was a note which read, “I hate Fujimaki.”
■ October 2012
Several students at the university reported seeing a man dressed all in black and carrying a container around the time of the incident. Shortly after a message was posted on a message board site claiming responsibility for the crime. The post was traced back to an internet cafe in Chiba Prefecture where security camera footage showed a man fitting the description of university witnesses, but revealed nothing otherwise distinguishing.
In Tokyo, customers are required to show identification before using internet cafes due to the large volume of criminal activity taking place through them. However, the man responsible for this incident knew that Chiba Prefecture had no such regulation and made his statement from there.
Then, on 15 October a threatening letter was delivered to Fujimaki’s former high school which also reportedly contained a “white powder.” By the end of the month, similar letters were sent to broadcasters in Tokyo and Osaka that aired the anime version of Kuroko’s Basketball. In each, incident the letters were postmarked from outside the destination’s prefecture which made it impossible for authorities to track accurately.
■ Kuroko’s Basketball

Although the manga has inspired some independently made yaoi (homoromantic fan fiction), there isn’t really any notably controversial subject matter in the story.
The series became hugely popular since beginning in Weekly Shonen Jump in December 2008. Currently, 25 volumes have been published selling 23 million copies.
■ End of 2012
In the following months, further threatening letters were being sent out to various events related to the Kuroko’s Basketball series in Tokyo and Chiba causing numerous cancellations or exclusions of the sports manga in the case of larger events.
In each case the letters were accompanied by a potentially poisonous substance or the threat of one. The wording of the letters seemed to alternate between Kanto and Kansai dialects but followed a pattern that suggested this was the work of a single person. Experts felt that the culprit was likely in their 30s or early 40s due to their knowledge of the internet and otaku culture.
On 17 January, 2013, an “End of Attack Declaration” for event venues was posted on a message board. However, in the following April more threats were made against events in Shiga and Kobe.
■ October, 2013
For a few months things went relatively quiet against Kuroko’s Basketball, but started up again in full force in October. On the 15th major video and CD rental chain Tsutaya along with several convenience stores received intimidating letters demanding the removal of all Kuroko’s Basketball related items. Tsutaya and 7-Eleven both complied to the demands and pulled products from their shelves.
On 4 November, Police warned Sophia University of a threatening message referring to a day they held a festival as “X-Day” but nothing unusual occurred. However, later that month a wafer snack from a convenience store in Urayasu City, Chiba was found to contain traces of toxic nicotine.
■ Glico Morinaga Incident
Among the scores of letters sent out was apparently a plethora of seemingly haphazard and conflicting “clues” about the criminal’s identity. According to Mainichi Shinbun who had received some threats themselves the “perpetrators are two old guys” and “renting a place in the Tokyotama area now.” The writer also referred to himself as Mofuku No Shinigami (Mourning’s Grim Reaper) but later on as Kaijin 801 Menso (The Monster with 801 Faces).
The Kaijin 801 Menso name is a reference to an unsolved crime in the 1980s involving a failed kidnapping attempt of the president of candy maker Ezaki Glico and subsequent threats of poisoning of Glico and Morinaga brand foods. The person or people responsible for this referred to themselves as Kaijin 21 Menso after a villain from Edogawa Rampo novels.
In the letter to Mainichi “the first revival of the Glico Morinaga incident in 30 years” was also written.
■ Arrest
On 15 December, 2013 36-year-old Hirofumi Watanabe was arrested on suspicion of interfering with business. According to police he was picked-up while putting letters into mail boxes in Shibuya, Tokyo. When caught, Watanabe reportedly admitted “I’m sorry. I lost.” and “I was working alone.”
Furthermore, according to police, inside Watanabe’s backpack were 20 threatening letters to organizers of a high school basketball tournament and Comiket demanding cancellations.
The authorities said that they were able to estimate the suspect’s appearance by the security footage of convenience stores even though he was wearing a mask and gloves. They added he was very careful not to leave any fingerprints as well.
■ Motive?
When asked why he held a grudge against Tadatoshi Fujimaki and/or Kuroko’s Basketball, Watanabe reportedly said that he never met the manga artist but “was jealous of his success.” This was also alluded to in a letter to Mainichi which read, “Fujimaki who lived a blessed life, and I who have never experienced anyone’s love.”
Although arrested in Tokyo, Watanabe is a resident of Osaka. He stands accused of sending over 400 letters of intimidation to businesses, events, and the media over a two year span causing several cancellations and 7-Eleven to recall goods from 1,500 of their stores. Although this ordeal seemed intended to destroy Kuroko’s Basketball, ironically this has made the manga and anime title the top story across the country.
Source: Yahoo! News Japan, Mainichi Shinbun 1, 2
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