Masaru Kashima is a character who appears in the Kurosagi franchise, originally introduced in the manga and later depicted in live-action adaptations. He serves as the newly appointed assistant inspector of the East Tokyo Department, specifically assigned to handle intellectual crimes. His background is marked by a personal connection to swindling: his paternal uncle was a swindler, a fact that led to his adoption by his mother's relatives. In order to pursue his deep-seated hatred of fraudsters without the burden of his family history, he arranged to have his own death faked at the age of two, thereby creating a completely new identity. Kashima's personality is defined by a strong sense of self-righteousness and a single-minded dedication to restoring law and order in Tokyo. Once he learns about Koshiro Kurosaki, the Black Swindler who targets only other swindlers, Kashima becomes obsessively focused on apprehending him. This fixation drives much of his role in the story: he acts as a persistent law-enforcement antagonist who clashes with Kurosaki's vigilante methods, even though both characters ultimately oppose criminal fraud. Kashima's key relationship is with Kurosaki, whom he regards as a criminal to be caught, creating a cat-and-mouse dynamic throughout the series. While the character does not undergo a dramatic transformation, his involvement pushes Kurosaki to operate more carefully and highlights the moral ambiguity of using illegal means to achieve justice. In terms of abilities, Kashima is portrayed as a diligent and intelligent investigator who uses his official position and resources to track Kurosaki's activities, though he is consistently outmaneuvered by the Black Swindler's expertise.