Ron Kamonohashi
| Company type | Manga series |
|---|---|
| Industry | Publishing, Entertainment |
| Founded | October 11, 2020 |
| Founder | Akira Amano |
| Fate | Ongoing (manga), anime adaptation aired 2023, second season scheduled for 2024 |
| Headquarters | Tokyo , Japan |
Area served | Worldwide (digital and anime streaming) |
Key people | Akira Amano (creator), Diomedéa (anime studio), Shōta Ihata (director) |
| Products | Manga, Anime, Stage play |
| Owner | Shueisha |
| Parent | Shueisha |
| Website | shonenjumpplus |
is a manga series from Japan created by Akira Amano. It was serialized in Shueisha's digital magazine Shōnen Jump+ between October 2020 and July 2025, totaling 17 volumes as of June 2025. The English version is also available through Shueisha's Manga Plus service.
The anime adaptation produced by Diomedéa aired from October to December 2023, with a second season scheduled to premiere in October 2024.
Premise
The story centers on Ron Kamonohashi, an unconventional private detective, and Totomaru Isshiki, an inexperienced police officer, who collaborate to solve criminal cases. Five years prior, Ron was the top graduate of the Detective Training Academy Blue but lost his detective license after being held accountable for the fatal "Bloody Field Trip" incident. Since then, he has lived in seclusion. Totomaru recruits Ron to assist with investigations, taking credit for the resolutions Ron uncovers.
Main characters
- A sixth-generation heir of Sherlock Holmes and ninth-generation descendant of James Moriarty. After losing his license due to the "Bloody Field Trip," Ron experiences a compulsive reaction when hearing murder confessions, compelling perpetrators toward suicide.
- A detective with the Metropolitan Police who gains recognition by claiming credit for cases solved by Ron. Ron refers to him as .
- Totomaru's superior officer at the Metropolitan Police. Although typically serious, she secretly harbors feelings for Ron.
- A famous neurosurgeon known for her clumsiness and frequent injuries. She develops medications aimed at suppressing Ron's "culprit-killing" compulsion, though these come with side effects.
- A detail-oriented detective from the Aichi Prefectural Police, holding the highest number of solved cases nationally and formerly a colleague of Amamiya.
- A crime journalist who supports Totomaru and Ron with investigative research. She admires Totomaru but dislikes Ron.
- An American who transferred to Blue Academy shortly before the "Bloody Field Trip," claiming to be friends with Ron. He is later revealed as an assistant to the Holmes family and regarded as an adopted son by Ron's mother.
Blue
The in England stands as the world's premier detective training academy.
- The tracking instructor at Blue tasked with investigating Ron's breach of his detective ban but actually seeks his help in locating his missing brother. Spitz befriends both Ron and Totomaru and aids them on multiple cases.
- The locked room instructor at Blue and one of fewer than ten individuals worldwide holding an S-rank detective license.
- Fin's bodyguard and fellow Blue graduate attending alongside Ron. He is later revealed as an informant for the M. Family within Blue.
- The anatomy instructor at Blue suspected in fifteen murder cases, one leading to his demotion from S-rank to A-rank detective.
- The principal of Blue and a close friend of Ron's parents. She discreetly informs Ron about the M. Family's involvement in the Bloody Field Trip while aware of an informant operating within Blue.
- The closed circle instructor at Blue.
- The top-ranked student at Blue, son of a vice-chairman of the World Detective Alliance and descendant of Blue’s founding principal.
- The second-ranked student at Blue, easily identified by her rabbit-ear headband.
- A top student attending on a scholarship under John Grizzly.
- A leading student enrolled at Blue.
M. Family
The , also referred to as the , represents a notorious criminal organization and stands as the primary adversary to the Holmes detective lineage.
- Milo's uncle, whose true name is .
- The fourth offspring, who specializes in the art of disguise. Following an unsuccessful operation, Milo commands an assassin to eliminate her; however, she survives and recuperates. Winter subsequently severs ties with Milo, harboring resentment for his role in their younger sister Alice's death.
- The eldest sibling and leader of the M. Family, responsible for killing his sister Alice to assume control. After being defeated by Ron, Milo faces an assault ordered by the "new boss," later unveiled as Alice herself, who survived due to tampering with the weapon before Milo fired. Displeased by Milo's emotional response after the incident, Alice intends to take over leadership of the M. Family upon reaching 17 years of age.
- The youngest member, initially presumed deceased. Alice reappears disguised as , nicknamed "Billy Goji," a top-performing student at Blue who perpetrates multiple murders before escaping custody once her true identity is uncovered.
World Detective Alliance
- Head of the Japanese Branch of the World Detective Alliance, a junior classmate of Ron at Blue, and son of Kiku, a police officer and Ron’s acquaintance.
Manga
Ron Kamonohashi: Deranged Detective, authored and illustrated by Akira Amano, began its bi-weekly serialization in Shueisha's digital magazine Shōnen Jump+ on October 11, 2020. The first part concluded on April 30, 2023; the second part commenced June 4 and is set to finish on July 6, 2025. Shueisha has compiled these chapters into standalone volumes, with seventeen volumes available as of June 4, 2025.
In North America, Shueisha holds the license for simultaneous digital publication via its Manga Plus platform.
Chapters Pending Compilation
These chapters have not yet been included in a volume release.
- 155–169.
- 170.
Anime
An anime adaptation was revealed on December 18, 2022. Produced by Diomedéa, it is directed by Shōta Ihata with scripts by Wataru Watari, character designs by Masakazu Ishikawa, and musical score composed by Yo Tsuji. The series was broadcast from October 2 to December 25, 2023, on Tokyo MX, AT-X, and other channels. The opening theme song is performed by Unison Square Garden, while the ending theme is by .
After the final episode aired, a second season was confirmed. It ran from October 7 to December 30, 2024. The opening theme for this season is , performed by , and the ending theme is , performed by Hockrockb.
Crunchyroll streamed the series internationally outside Asia under the title Ron Kamonohashi's Forbidden Deductions. Meanwhile, Medialink secured licensing rights for South Asia, Southeast Asia, and Oceania (excluding Australia and New Zealand), streaming it on its Ani-One Asia YouTube channel for Ultra subscribers.
Season 1 (2023)
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{{Episode list
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OriginalAirDate ={Start date 2023 12 18}
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Season 2 (2024)
{{Episode list │EpisodeNumber ═ 26 │EpisodeNumber2 ═ 13 │Title ═ The Case of the Highland Auberge Serial Murders (Part 4) │TranslitTitle ═ Kōgen Ōberuju Renzoku Satsujin Jiken【Kanketsuhen】 │NativeTitle ═ 高原オーベルジュ連続殺人事件【完結編】 │DirectedBy ═ Shōta Ihata & Shingo Tamaki │WrittenBy ═ Wataru Watari │Aux2 ═ Shōta Ihata │OriginalAirDate ═ │LineColor ═ 601B4A }}
Stage play
A stage adaptation was performed from November 1 to 4, 2024, at Tokyo's Nippon Seinenkan Hall, followed by shows on November 9 and 10 at Osaka's Sankei Hall Breeze. The production was both written and directed by Keita Kawajiri, featuring a musical score composed by Futoshi Arai.
Reception
In June 2021, Ron Kamonohashi: Deranged Detective earned a nomination in the Best Web Manga category for the seventh Next Manga Award, placing 14th among 50 contenders. Esteemed mystery authors Rintaro Norizuki, Masaki Tsuji, and Sako Aizawa—each previously ranked highly in Kono Mystery ga Sugoi!—endorsed the series. Aizawa described it as a "genuine mystery manga suited for the modern age," emphasizing its brisk narrative and astute deductive elements. Ryoko Fukuda of Real Sound likened the interplay between Ron and Toto to the classic comedic duo of straight man and comic, praising its lively and rapid storytelling style.