Juumonji Incident

The Juumonji Incident is a case featured in of the Classic Literature Club series and episodes 12-17 of the Hyouka anime series.

Kamiyama High School annually holds a cultural festival commonly known as "Kanya Festival". But this year a thief calling themself "Juumonji" appears, stealing items from different school clubs, leaving behind a card and the festival brochure.

Classic Lit Club have finished their anthology and intends to present it as their attraction for the festival. However, Mayaka Ibara made a mistake and ordered excessive copies, which causes trouble for the club, because they need to sell all copies. Eventually, Houtarou Oreki and his friends gets convinced that by solving the Juumonji incident, they might be able to attract people in order to sell all the copies of their anthology.

Background
Kamiyama High School's Classic Lit Club has a long-established tradition of publishing its annual anthology called Hyouka. Current club members Houtarou Oreki, Eru Chitanda, Mayaka Ibara and Satoshi Fukube decide to continue that tradition by publishing new issue of the anthology with the story of Eru's uncle expulsion and his influence on the Classic Lit Club.

Due to Mayaka's mistake during her order of anthologies, the club purchased more copies of the anthology than was needed. Because of that, Classic Lit Club was in dire need to sell more anthologies than it was expected. Each of the members did their best to make for it.

During her wandering around the school, Eru met her friend called Kaho Juumonji. Kaho told her about the case of her missing Tarot card, mysteriously stolen from her. Shortly after that, Eru discovers that Kaho is not the only one who found her stuff missing. Therefore, Houtarou got a new mystery to solve.

First day of Kanya Festival
At the first day of Kanya Festival, Eru is wandering around the school looking for other clubs which would allow them to sell Hyouka at their booths, and other ways to promote sales of it. While doing so, she met her friend, Kaho Juumonji from the Fortune Telling Club. Kaho told her that she lost a card,, and the culprit left a note signed by "Juumonji" between the pages of the Kanya Festival brochure left. Meanwhile, Satoshi participated in the Quiz Research Society's Quiz Trial 7 to promote Hyouka. During the trial time he met his acquaintance, Koreyuki Tani from Go Club, who was among the competitors. Koreyuki told him that Go Club suffered from a theft of a few Go stone pieces.

While his club members had been busy, Houtarou was sitting in the clubroom waiting for customers to come. He managed to sell one copy to a punk-like student who turned to be a member of Clothing Research Society, and gave him a broken fountain pen he received from his sister, Tomoe. That started a series of exchanges like in the "" folk tale. Houtarou traded pen for a backstage pass. Next, he exchanged the pin from the backstage pass for a water gun from a Gardening Club Member. After that, Houtarou traded water gun and in addition a copy of Hyouka for two bags of cookies and a bag of flour from members of the Confectionery Club.

Second Day of Kanya Festival
At the start of the second day of Kanya Festival, Satoshi had a brief conversation with Jirou Tanabe, president of the school's Executive Committee about the mysterious disappearance of some stone pieces from The Go Club. In response, Tanabe told him that The A Capella Club had suffered from the same thing, as they lost a drink. In order to promote Hyouka, The Classics Club members (except Houtarou) competed in the Cooking Research Society's cooking contest called "Wild Fire". During the competition, Mayaka discovered that Classics Club's cooking station had a ladle missing, which caused her some trouble. Despite that, Classics Club Team won the first place. After the competition, Cooking Club President apologized to Classics Club members for the trouble. That loss was quite strange, because Cooking RS double checked all stations before the contest.

Meanwhile, Eru found the same note from Juumonji under a cutting board which claimed they took a ladle from the cooking club that was missing from the Classic Club's cooking station. And then, she brings the note to Houtarou who is eating lunch and ask him about it. At first, Houtarou is not interested about it and dismissed it as someone who is bored to do such a thing but then Satoshi and Eru added that The Acapella Club, Go Club and Fortune Telling Club also had something similar happened. And, when Eru was about to say she's curious about Juumonji, Houtarou stopped her and reminded her that they're too busy selling all the copies of Hyouka to investigate it. Satoshi interrupted him and said that promoting them through events is not enough and so they would solve the Juumonji mystery to promote Hyouka by announcing it in tomorrow's school-wide radio broadcast with Houtarou as the detective. Houtarou refused to do so, but, he also thought that it's impossible to find out Juumonji's true identity from thousands of people at the Kanya Festival.

After a moment, Houtarou then asked which clubs that have been targeted so far. Satoshi mentioned Acapella Club, Cooking Club, Go Club and Eru also add Fortune Telling Club. Houtarou, Satoshi and Mayaka realized that Juumonji's Modus Operandi is based on Japanese Alphabet which is similar to Agatha Christie's The A.B.C. Murders. And since all the victims in The A.B.C. Murders were murdered in alphabetical order of their names and towns they were murdered at, they compared all the clubs and their lost items which confirmed that the pattern was very identical. Houtarou figured out that the thefts were conducted following one single pattern:
 * A Capella Club (アカペラ部) lost a drink (ドリンク)
 * Go Club (囲碁部) lost stone pieces (石)
 * Fortune Telling Club (占い研) lost a Tarot card, The Wheel of Fortune (運命の輪)
 * Gardening Club (園芸部) lost a water gun based on an AK assault rifle (AK)
 * Cooking Research Society (お料理研) lost a ladle (お玉)

Houtarou also suggested that the "Juumonji" signature left by the thief is not a name, but rather the phrase Juumoji meaning "10 letters" (十文字). Therefore, Houtarou concluded, the thief will continue to steal things from clubs according to (traditional system ordering kana by their component phonemes, roughly analogous to alphabetical order). That included clubs beginning with A, I, U, E, O, Ka, Ki, Ku, Ke, Ko. This gave the Classics Club (古典部) opportunity to promote themselves, since they could become the last victim.

Eru went to Wall Newspaper Club (壁新聞部) to warn them, and was told that they lost a utility knife (カッターナイフ) . Meanwhile, Satoshi investigated other clubs for more info, and found out that A Capella Club (Akapera-bu) lost an apple juice (アップルジュース). Satoshi assumed that Juumoji's next target would be the Magic Club (奇術部) and decided to go to their magic show to catch the thief in the act. But, Juumoji managed to beat him by stealing a candle (キャンドル) before the performance even started. Mayaka who was in the clubroom, decided to return to the Manga Research Society, and Houtarou asked her to trade something for the bag of flour he gave to her during the cooking contest earlier. Mayaka gave him a handheld mirror.

Third Day of Kanya Festival
At the last day of Kanya Festival, everyone at school is more excited than ever since knowing about Juumoji's theft incident from the school's wall newspaper and many amateur detectives of the school attempted to catch them in order to be featured at the school's wall newspaper. Satoshi is preparing another ambush at the Global Act Club since Juumoji's next target would be a club that starts with "Ku". But they never came and instead targeted the Light Music Club (けいおん部) and stole a string (弦). On the other hand, Houtarou's big sister, Tomoe came to see him and buy one copy of Hyouka and then she also traded the mirror Houtarou got from Mayaka with a doujinshi manga titled "A Corpse by Evening" and told him that it's up to him whether or not to pass the time with it before she leaves. Houtarou read the author pen name Anshinin Takuha and also read the afterword at the last page of the manga noticing that Anshinin Takuha is a group name. And he also noticed they mentioned Kudryavka's Order at the afterword which catches his attention, after that he started reading it.

Meanwhile, Eru is currently trying to ask the president of Broadcast Club to promote Hyouka and the president Yoshino coincidentally wanted to invite her as a guest to his radio show in the afternoon as the president of the club that could potentially become Juumoji's last victim which Eru gladly accept. After returning to the clubroom, Eru became curious about the manga Houtarou just finished reading and look at it much closer where she noticed the art style is similar to the poster pinned at the meeting room. She immediately went to compare them where she meet up with Mayaka on the way. After hearing Eru that the poster pinned at the meeting room and "A Corpse by Evening" could be drawn by the same person, she became interested and came along with her. She confirmed Eru's assumption and they asked Tanabe Jirou who drew the poster. And he told them that the student council president, Muneyoshi Kugayama drew it.

Eru and Mayaka returned to the clubroom and informed that the manga and the poster was drawn by Muneyoshi Kugayama. Houtarou seems to be confused by that name, so everyone told him that he is the student council president. Houtarou misread his name as Rikuyama all this time hence the confusion. And he also asked that if the president is the artist for Anshinin Takuha, but then Satoshi corrected the spelling as Ajimu Takuha which is also pointed by the Romaji written next to the Kanji. Mayaka confirmed it and also informed them that the writer of the manga is Anjou Haruna which she found out from the Manga Research Society's club president.

And then, Eru informed everyone that she was invited to the radio show in the afternoon and Satoshi then offer her advices on being a guest of a talk show. After that, Houtarou asked Satoshi to talk with him for a bit outside. Houtarou told Satoshi that he hasn't figured something relevant but he believed there's a reason behind the incident. So, Satoshi asked him whether he find a connection between all the clubs that have become victims or did Juumoji make a mistake. But, Houtarou denied them. Satoshi seems surprised that Houtarou would find Juumoji among thousands of suspects without any connections or mistakes which he thought impossible. But Houtarou then said he just wanted to put together his thoughts and so he pointed out a few things.

First, Why would Juumoji stole ten items from ten clubs?. Second, Why would they left a note each time they committed the crime?. Third, why are they consistently used the word "lost" instead of "taken" at the note?. Fourth, why would they left a Kanya Festival Brochure? since they're not the only thing that listed all the clubs at school. Fifth, Why the Gardening Club and the Cooking Club? since there are other clubs that starts with "E" and "O". Sixth, why would they skipped "Ku" and go straight to "Ke"? since that would mean they broke their own Modus Operandi. And lastly, Kudryavka's Order from the afterword of "A Corpse by Evening". Satoshi argued that the manga is irrelevant but Houtarou believed it's relevant in a way. From the title and the afterword, it is implied that the manga will be based on Agatha Christie's famous story which could've been "The A.B.C Murders". Houtarou asked Satoshi if a manga titled Kudryavka's Order is sold in the festival. But, Satoshi hasn't heard about it and Mayaka didn't say anything about it. Houtarou believed that Kudryavka's Order is somehow connected to the Juumoji incident since both of them are based on The A.B.C. Murders as a common link and also the culprit is very serious about this since they made sure they don't disrupt other club's activities. And then, Satoshi left him and Houtarou started thinking after borrowing the Kanya festival brochure from Satoshi and asked him to prepare a completed manuscript as a bait for Juumoji.

The Climax of the Kanya Festival, the Truth Behind the Juumonji Incident, and Despair in Expectations
The school radio broadcast started with Eru answered to all the announcers shout out while promoting Hyouka and ask the other students to help them guard the completed manuscript that would be used to lure Juumoji. During this, Mayaka who was in the clubroom noticed that some of the copies of Hyouka disappeared although she dismissed it as being sent out somewhere else for sale. After that, The Classics Club's clubroom is now filled with a lot of people who are waiting for Juumoji which makes their anthologies started to sell well. However, after a few moments, everyone started to become impatient thinking there's no way Juumoji can steal the manuscript with a lot of people guarding it. Suddenly, Satoshi's phone is ringing which makes everyone surprised and while everyone's distracted the manuscript is suddenly on fire. Satoshi immediately extinguished it and claimed that they're defeated. Eru noticed there's water at the table where the manuscript is placed at and Mayaka also found Juumoji's note between the pages of a copy of Hyouka lying on the floor that goes like this "The Classic's Club completed manuscript has been lost. The ten letters has been achieved.". With that, the Kanya Festival ended with The Classics Club's defeat and Juumoji was never caught.

In a flashback, Satoshi was following Houtarou to the bike parking lot and witnessed something unbelievable. Houtarou confronted Tanabe Jirou whom he identified as Juumoji. Tanabe calmly admitted it and then Houtarou started explaining on how did he deduce Juumoji's true identity. Juumoji consistently used the word "Lost" instead of "Taken" in each notes that he left after the crime and he skipped "Ku" despite his Modus Operandi was based on the order of the first ten letters of Japanese Alphabet. Houtarou believed that the incident was actually a coded message to someone whose name starts with "Ku" and have already lost something that starts with "Ku" with the receiving party could decipher it.

Houtarou then continue explaining that the Juumoji Incident is based on Kudryavka's Order, a story based on Agatha Christie's The A.B.C. Murders. With this in mind, the recipient of the message is Kugayama Muneyoshi, the student council president and the artist of "A Corpse by Evening". Houtarou explained further that all of the victims so far aren't random but predetermined, the names of the clubs that became victims were written at a page of Kanya Festival Brochure in an alphabetical order with the name "Kugayama Muneyoshi" was written after the Magic Club which proved that Juumoji skipped "Ku" on purpose to refer to Kugayama Muneyoshi. And, the fact that the contents of the brochures can only be manipulated by the members of the Executive Committee, the list of suspects have been narrowed down from thousands to 20 people.

Based on a theory Houtarou could think of, Kugayama lost the script for Kudryavka's Order and Juumoji wanted to blame him for it using the incident as a message. By following the same pattern as the message from the notes, the culprit's message would be "Kugayama's Kudryavka's Order has been lost.". The afterword at the manga's last page implied that Ajimu Takuha is a pen name for a three person group consisted of Kugayama as the artist, Anjou Haruna as the writer, and an unnamed background illustration artist who also wrote the afterword. That makes three people who knew about Kudryavka's Order and that background artist is the only one who could be Juumoji. Lastly, Houtarou deduced that Ajimu Takuha is actually a combination of the first letters of each members' names with "A" and "Ha" for Anjou Haruna and "Ku" and "Mu" for Kugayama Muneyoshi. Excluding those letters, that leaves only "Ta" and "Ji". Juumoji's true identity is a second year or higher student, participant of last year's Kanya Festival, a member of the Executive Committee, someone whose first and last names starts with "Ta" and "Ji", and a friend of Kugayama who knew he could draw manga. The only one who fits the description is Tanabe Jirou, Kugayama's best friend and the president of the Executive Committee.

Lastly, Houtarou deduced that the pen name Ajimu Takuha is actually a combination of the first letters of each members' names. "A" and "Ha" for Anjou Haruna and "Ku" and "Mu" for Kugayama Muneyoshi and that leaves only "Ta" and "Ji". Juumoji's true identity is a second year or higher student, participant of last year's Kanya Festival, a member of the Executive Committee, someone whose first and last names starts with "Ta" and "Ji" and a friend of Kugayama who knew he could draw manga. The only one who fits the description is Tanabe Jirou.

Tanabe applauded Houtarou for his deduction. Houtarou asked him why would he do such a thing. Tanabe asked if he had a guess about it. Houtarou answered to keep Anjou Haruna's spirit alive after she transferred. Tanabe replied that that is also one of them and he wanted to mess around at the festival but the biggest reason was that he couldn't say it to Kugayama directly. After that, Houtarou blackmail him to buy 30 copies of Hyouka. He then made a deal with Tanabe. Tanabe would buy them under the Executive Committee's name to be sold at the school's website and also make the Classics Club as his last victim to boost the anthologies' sales for both sides' benefits. In exchange, not only Houtarou would keep silent about the incident, he and Satoshi would also provide assistance from the inside to conclude the incident with no problem.

For the assistance, Houtarou asked him to get some Sodium which he would slip between the manuscript's pages that would be guarded by a lot of students beforehand and also a water gun. After enough anthologies have been sold, Houtarou would signaled him to call Satoshi's phone for distraction and shoot the manuscript with the water pistol to make the sodium explode and burn the manuscript. Finally, Tanabe would slip the culprit's note inside one of the copies of Hyouka and drop it on the floor.

After that, Tanabe asked Houtarou curiously when he assumed Kugayama lost the script for Kudryavka's Order was his motive. Houtarou honestly claimed that it's just a theory with no proof and he actually can't think of anything that would give Tanabe a motive. Tanabe figured that Houtarou wouldn't understand it. He then explained that Kugayama is a talented artist, even more talented than him in drawing. Tanabe wanted Kugayama to continue drawing since he believed he could draw something better than "A Corpse by Evening". But, for Kugayama, drawing manga is something that he did for fun that time and he didn't want to continue drawing at all which he thought as a waste of talent.

Houtarou figured out Tanabe's real message to Kugayama was "Kugayama, have you ever read Kudryavka's Order?". And Tanabe was impressed once again by Houtarou.

Conclusion
After the closing ceremony of the Kanya Festival, The Classics Club have sold almost every copies of Hyouka and only four copies remaining. And so, Satoshi suggested they each buy one copy which makes them officially sold out and Eru wanted to know more about the Juumoji Incident and stare at Houtarou with that in mind and Satoshi intentionally tell Eru that Houtarou have figured it out and also suggested to talk about it over celebration for their effort at selling Hyouka and Eru invited them to her house for the celebration.