No Mercy

黑岩泪香Jan 2026

3.8

Word count: 23K words
Chapters: 6

Summary

In July of the twenty-second year of Meiji, a horribly mutilated unidentified male corpse was found in a river near the former site of the Tsukiji Naval Academy, the body covered in wounds and bearing no identification whatsoever. Detective Tanimada, drawing on experience, inferred that the case was connected to a gambling den and to a curly-haired woman named Otsugu, and launched an investigation. The young detective Ōtomo took a different path: analyzing the three strands of hair clenched in the dead man's hand and applying science and logical reasoning, he discovered that the hair was not naturally curly and that it included both reversed hairs and dyed white hairs, leading him to suspect that the true culprit was a Chinese man who wore a wig and dyed his hair white. Tanimada succeeded in capturing Otsugu, while Ōtomo zeroed in on a Chinese man named Chen Shining who matched the description. As Otsugu's confession unfolded, the identity of the dead man, the brotherhood between Chen Shining and the deceased, and the emotional entanglements behind it all gradually came to light.

Editor's review

Taking as its starting point an unidentified male corpse found in Tsukiji, Tokyo, in the twenty-second year of Meiji, Mukuzen (Miserable) draws readers into the urban underworld of Japan's early modernization. Kuroiwa Ruikō, an important translator and creator of detective fiction in the Meiji era, here combines the evidentiary pleasures of honkaku mystery with the richness of period custom. The two detectives form a sharp contrast: Tanimada relies on street experience and personal networks to pursue the gambling den and the curly-haired woman Otsugu, while Ōtomo begins with the three strands of hair clenched in the dead man's hand, reasoning scientifically from details such as curl, reversed hairs, and dyeing, and ultimately pointing suspicion at a Chinese man named Chen Shining who wore a wig and dyed his hair white. Behind the case lie the dead man's identity, a brotherly relationship, and emotional entanglements, so that the deduction is not merely puzzle-solving but also raises questions of a cross-sea population and identity disguise. Readers can enjoy the pleasure of clues converging layer by layer while also sensing the Meiji imagination of "scientific investigation." Suitable for readers interested in early Japanese detective fiction, Meiji custom, or the origins of honkaku mystery.

Who it's for

A good fit for

Readers who enjoy honkaku mystery and value physical evidence and logical deduction
Those interested in the social customs and urban spaces of Meiji-era Japan
Readers studying the history of detective fiction who want to understand Kuroiwa Ruikō's creative profile
General mystery fans willing to follow the contrasting investigative rhythms of two detectives

Not a good fit for

Readers who prefer fast-paced modern suspense with strong twists
Readers impatient with old-era settings and detailed historical research
Readers hoping for abundant action scenes or psychological thrills

Reading tips

Begin with the opening passage in which the corpse is found in the river, note physical evidence such as the three strands of hair, and then follow Ōtomo's deductions point by point.
Read Tanimada's street visits and Ōtomo's scientific evidence-gathering as two parallel lines, noting how the author makes the two methods complement each other.
After reading Otsugu's confession, look back at the earlier foreshadowing about the gambling den and the curly hair to appreciate how completely the clues are recovered.
Together with the ending's account of the dead man's identity and the brotherly relationship, consider the social significance of identity disguise among cross-sea populations in the Meiji period.

版权信息
序
上篇：疑团（上）
上篇：疑团（下）
中篇：忖度
下篇：冰解

FAQ

Is this book an original work by Kuroiwa Ruikō or a translation?

Sources list Kuroiwa Ruikō as the author, and the work is set in Tokyo in the twenty-second year of Meiji. Kuroiwa Ruikō is known for translating and creating detective fiction, so this book should be regarded as a detective novel under his name; whether it is wholly original or an adaptation should be confirmed with the publisher's notes.

What role do the three strands of hair play in solving the case?

The three strands of hair clenched in the dead man's hand are the key physical evidence of the book. Through analysis, Ōtomo discovers that the hair is not naturally curly and that it includes reversed hairs and dyed white hairs, from which he infers that the true culprit may have worn a wig and dyed his hair white, thus pointing suspicion at the Chinese man Chen Shining.

How do the two detectives' methods differ?

Tanimada relies on experience and personal networks to pursue the gambling den and the curly-haired woman Otsugu, emphasizing street visits; Ōtomo starts from minute physical evidence such as hair and uses scientific analysis and logical reasoning to identify the suspect. The two lines advance in parallel and finally converge in the confession.

Do I need to know Meiji history before reading?

Not systematically, but knowing that the story is set in Tokyo in the twenty-second year of Meiji and involves urban spaces such as the area near the former Tsukiji Naval Academy and a gambling den will make it easier to enter the atmosphere. The book's depictions of period custom are themselves part of the reading pleasure.

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About the author

黑岩泪香 Author

Kuroiwa Ruiko was a Japanese journalist and novelist. Publicly available information about his life is limited, and his nationality and the exact years of his birth and death are not clearly recorded. The library currently holds only one work by him, Muzan (The Cruelty), which is classified as mystery and detective fiction, and no representative work is listed. Judging from this surviving title, Kuroiwa Ruiko's writing emphasizes tense plotting and a gloomy atmosphere, skilfully building suspense between crime and the darker sides of human nature, with the flavor of early Japanese popular detective fiction. Long active in the newspaper world, he worked both as a translator and as a writer, and helped promote the translation and popularity of detective fiction in Japan. Because the sources are scattered, the full range of his work and his literary standing remain to be examined; readers may begin with Muzan to sense the tone and narrative rhythm of Meiji-era translated and adapted detective fiction.