Detective Kiyokawa of the Metropolitan Police Department investigates enigmatic cases surrounding the Yoshinaga household, approaching each mystery with unwavering seriousness and methodical precision. His dedication to justice drives him to dissect complexities through sharp observation and logical deduction, uncovering overlooked details that crack even the most convoluted scenarios.

Professionally reserved, he occasionally reveals a dry wit or fleeting warmth during interactions, balancing his stern demeanor. While his cases often intersect with supernatural phenomena—particularly those involving the household’s alchemically bound gargoyle—he adheres to pragmatic principles, treating otherworldly elements as puzzles to solve rather than mysteries to embrace.

His past remains undisclosed, and his role persists as a steadfast investigator who advances narratives by untangling truth from obscurity. Secondary yet pivotal, he operates without personal arcs or expanded backstory, serving as an anchor of rationality within the unfolding chaos.