Kouko Miyanoshita

Kouko Miyanoshita (Japanese: 宮乃下 耕子; born March 30 2003), given name also romanized as Kōko or occasionally Koko, is a Japanese private investigator.[1] She is notable both for starting her career at a young age, and for her involvement with a number of high-profile murder cases, both in Japan and internationally.[2] She is additionally known for being Hope's Peak University's "Ultimate Detective."[3][4][5] Miyanoshita is responsible for solving at least 319 murder cases (65 of which were considered cold cases), 94 missing persons cases, and 72 cases of other forms of crime such as burglary or assault.[6][7][8][9] She has been involved with and contributed to several cases outside of these.[10]

Early Life and Career

Miyanoshita was born in the Ōno District of Gifu Prefecture in a small, unidentified community (presumed to be one of the six that later merged into the city of Takayama).[3][11] Miyanoshita reports living a sheltered childhood, with her mother being sick constantly and her father being absent for work.[12] Miyanoshita was unable to connect with the other children of her community, but found solace in literature.[13] She often purchased books from a used bookstore found in the community, though her small allowance made her collection limited to begin.[14] However, the store often had sales on crime and detective novels they received in bulk, and Miyanoshita's parent, Sakaki Watabiki (known for being Hope's Peak University's "Ultimate Forensic Pathologist") often bought her several novels at once for birthdays or other celebrations.[15][16] She gained a deep passion for mystery fiction from reading these novels and similarly-styled manga, and would often play pretend as a detective around her community, much to the annoyance of several locals.[14][17]

At the age of 13, while watching the news with her parent, she learned of the Murder of Haruhiko Nakakuma, a murder case which occurred at a secluded inn in the nearby Toyama Prefecture on December 13th, 1931.[18][19][20] The cold case was notable for having several potential suspects present at the inn, but all with solid alibis and a lack of perceivable motive. Being unfamiliar with the idea of a murder case going unsolved for so long, Miyanoshita became obsessed with the case, and began looking into the previous investigations surrounding the murder.[21]

While doing her research, Miyanoshita happened to re-read the famous crime novel Murder on the Orient Express, which she claimed significantly aided her deduction.[22] She later went to the police with her proposed solution. While she was initially dismissed, her proposal was later sent to the larger Toyama Prefectural Police. After an investigation was reopened, forensic evidence indicated that the case matched Miyanoshita's proposal, and the case was later declared officially closed.[20][23] While the culprits had all since passed, Nakakuma's surviving family reported immense gratification from finally knowing the truth.[24]

After discovering her solution of the Murder of Haruhiko Nakakuma being verified, Miyanoshita began privately investigating several other murder cases, such as those of Fusao Yoshimoto, Sayuri Ishizaki, and the Tominaga Family.[25][26][27] During the course of her investigations, she made a revision of English priest and author Ronald Knox's Ten Rules For Detective Fiction, using them as guidelines for her deductions.[28] She once again submitted her solutions to the respective prefectural police forces, and all but one of them were later verified.[29][30]

Around this time, Miyanoshita made her first public appearance by taking on the case of the Murder of Juusuke Tsumura. The Tsumura family reported dissatisfaction with the police's handling of the case, possibly because Tsumura was an open critic of local law enforcement.[31] Miyanoshita met with the family for the details surrounding the murder, and spent the next month performing investigations and interviews with suspects and witnesses, as well as, according to herself, reading mystery novels for bouts of inspiration.[32] She eventually turned who she believed to be the culprit, Ryou Osada, over to the family, who then turned him into the police. He was later found guilty.[33] This is what many people, including Miyanoshita herself, consider the beginning of Miyanoshita's proper detective career.[2][34][35]

The Kagasawa Family Murders

One of Miyanoshita's most infamous cases is that of the Kagasawa Family Murders.[36] On June 25th, 2018, while Tarou Kagasawa and his daughter Chiaki Kagasawa were supposedly on vacation in Nagano Prefecture, police found the dismembered torso of Tarou at the Asahigaoka Inn.[37] Blood-stained clothes and accessories belonging to Chiaki were also found around the room, but Chiaki was never found.[38][39] A note placed near Tarou's body led investigators to find Tarou's remaining body parts, buried at various locations across Japan, with subsequent notes all hinting to the next location. The only body part which remains missing is Tarou's left hand, which the second-to-last note claims will "reveal the truth of everything."[40] This case is infamous, both for its brutality and complexity, and for Miyanoshita herself claiming that it is among the only cases she has not been able to solve.[41]

Acceptance to Hope's Peak University

In 2019, Miyanoshita investigated the murder of Klaas Speelman, a Dutch student at Hope's Peak University known for being the "Ultimate Somnologist," who was poisoned in his sleep by a step-brother seeking his inheritance.[42][43] The quiet nature of the investigation, as well as the fact that the culprit was not another student, allowed the case to stake off the controversy previous murder cases involving HPU had earned.[44][45][46] As such, after her investigation, Miyanoshita was scouted for Hope's Peak University, and soon began attending the school as its "Ultimate Detective."[47][48]

  1. Fitzsimons, William. "Japan's Real-Life Sherlock Holmes."
  2. Watanabe, Rafael. "Youngest Private Detective in History? The Rise of Investigator Miyanoshita."
  3. Ishigaki, Kon. "Who is Kouko Miyanoshita?"
  4. Burns, Charlie. "History of Ultimate Detectives at Hope's Peak University."
  5. Maitra, Tamanna. "A Look at the Current Student Body of H.P.U."
  6. Orihara, Tatsuhiko. "The Career of Detective Miyanoshita."
  7. Castelli, Sadie. "Efficacy of Private Investigators in Japan."
  8. Makishima, Yuya. "Hope's Peak Detectives Outside of their School Life."
  9. Kunikida, Hibari. "Police or Non-Affiliated Detectives: Who Is More Effective?"
  10. Nogami, Kenta. "A Summary of the 'Miyanoshita Cases.'"
  11. Ushiroya, Akane. "The Early Life of the 'Great Detective.'"
  12. Sono, Ryūtarō. "Looking Back on an Interview with Detective Miyanoshita."
  13. Kington, A. Q. "Before They Were Ultimates—Talented Students' Lives Before HPU."
  14. Poincaré, Jean-Loup. "Connections Between Real-World Investigators and a Love of Crime Fiction."
  15. Yoshida, Sei. "A Short Biography on Dr. Sakaki Watabiki."
  16. Wodajo, Bekele. "Lineages of Talent: How Children of Ultimates Became Ultimates Themselves."
  17. Shinkawa, Yasuko. "How Investigator Miyanoshita Gained Her Love for Detective Fiction."
  18. Ibuse, Daiji. "Brutal Killing at Inn in Toyama Prefecture." (1931)
  19. Tokiyuki, Sōsuke. "Baffling Murder in Remote Toyama Inn Makes Headlines Across the Prefecture." (1931)
  20. Jo, Seung-hyun. "History of the Haruhiko Nakakuma Case."
  21. Otowa, Azami. "Miyanoshita Becomes a Detective."
  22. Laisné, Lio. "How A British Crime Novel Helped Solve This Impossible Murder Case."
  23. Takeuchi, Koharu. "Near 90-Year Cold Case Murder Finally Solved."
  24. Ichinose, Ren. "The Murderers Will Never Face Justice, Yet Nakakuma Family Members Still in Tears Over Finally Receiving the Truth."
  25. Kanzaki, Mikoto. "Murdered in the Midst of Prayer: What Actually Happened to Fusao Yoshimoto."
  26. Kugayama, Yoshiki. "The Truth of Sayuri Ishizaki's Fiery Demise Revealed by Private Detective."
  27. Hiiragi, Kintarō. "Picked Off One-by-One: Investigator Tackles Lakeside Murder of the Tominaga Family."
  28. Yanagise, Kasumi. "'No Secret Passages Without Reason, I'm Afraid.' Detective Miyanoshita Publishes Controversial Revisal of Old Writer's Rules of Mystery in Light of the Recent 'John Doe' Case."
  29. Amakawa, Yuri. "Yoshimoto, Ishizaki, Tominaga—Detective Miyanoshita's Baffling Findings."
  30. Sawarabi, Chihaya. "Prefectural Police Cautiously Put Investigator Miyanoshita's Report, Which Suggests an 11-Year Old Committed the Crime, on Hold."
  31. Gokō, Mana. "Journalists Cite Juusuke Tsumura's Criticism of Law Enforcement for Poor Handling of Murder Investigation."
  32. Saibara, Naoya. "How the Murder of Juusuke Tsumura Was Solved."
  33. Maejima, Akira. "Culprit of Brutal Sickle Killing Finally Arrested."
  34. Fukamachi, Shion. "Mysterious Investigator 'Kouko Miyanoshita' Makes Her First Public Appearance."
  35. Gallagher, Lyric. "How Detective Miyanoshita Views Her Path to HPU."
  36. Hu, Xiaofeng. "The Kagasawa Family Murders: Perhaps the Most Incomprehensible 'Miyanoshita Case.'"
  37. Hitofumi, Kenzō. "Dismembered Torso Discovered at Asahigaoka Inn in Nagano." (2018)
  38. Yamano, Kiyomaru. "Asahigaoka Torso Identified, but Daughter of the Deceased Has Not Been Found." (2018)
  39. Soga, Hiromi. "'Come And Save Her From Oblivion!' Kagasawa Child Remains Missing."
  40. Shichijō, Eisuke. "Latest Discovered Kagasawa Murders Note Claims that 'Everything Will Be Revealed' If Investigators Find Left Hand."
  41. Padilla, Zoilo. "Most Unfathomable Unsolved Murder Cases."
  42. Nakamura, Daniël. "HPU's Ultimate Somnologist Found Dead, Poisoned By Sleeping Pills." (2019)
  43. Meulenbelt, Carolijn. "Step-Brother of Klaas Speelman Implicated in His Sleeping Pill Murder." (2019)
  44. Dietsche, Artur. "Hope's Peak University Staff Do Not Foresee Klaas Speelman's Murder to Cause Significant Controversy."
  45. Novaković, Tomislav. "Liling Quan and Klaas Speelman—Discrepancy in Reactions?"
  46. Gaston, Sara. "Comparing the HPU Responses to Murders of Ultimate Students."
  47. Terashima, Ikuko. "Famed Young Private Detective Kouko Miyanoshita Accepted into Hope's Peak University."
  48. Wilde, Michelle. "The Upcoming First Years of Hope's Peak University."
Name: Kouko Miyanoshita (宮乃下 耕子)
Ultimate: Detective
Age: 20
Birthday: March 30, 2003
Pronouns: She/Her
Class Number: 127
Nationality: Japanese
Height: 159 cm, 5'2"
Weight: 64 kg, 141 lbs