Hideomi Iba is a secret agent of Japan's Ministry of the Army Military Affairs Bureau, stationed at the significant Kudan Satellite Office. He operates under deep cover as a writer for *Monthly Real Crime* magazine, using this identity to conduct investigations. Recalled to Japan from the Harbin Military Secret Service due to intelligence linking the Ministry of Home Affairs with foreign entities, he focuses his inquiries on V Shipping Company and Alma Trading Company.

He possesses black hair and grey eyes, projecting a professional demeanor. Iba's investigative approach prioritizes caution against forming premature conclusions. He corrected an associate who blamed Kuratake alone for an incident, emphasizing the Hyakko Party's potential involvement and advising against using his military title while in civilian attire.

During an official briefing, Iba expressed skepticism regarding Hyakko Party involvement in Kuratake's jailbreak. He reported the Home Affairs Ministry granting operational permissions to a foreign group, prompting his commanding officer to question the military's action timeline. Iba confirmed military operations had already commenced.

His intellect is demonstrated by recalling a map's details after viewing it for only seconds before its removal, an ability aiding his strategic assessments. While his activities intersect with broader conflicts involving vampire hunters and vampire factions, his direct involvement centers on investigating human criminal elements and potential threats to national stability.