According to Good Girls Scans:
Ichiro works for the Tokyo Metropolitan Police Department Public Security Bureau as an investigator. Upon receiving orders from his superior, he approaches Shiro, a yakuza who is engaging in sexual relationships with politicians, to investigate and monitor him. However, he soon learns that Shiro is the younger brother of his senior investigator, whom he has been searching for after their unexplained disappearance. To uncover the truth behind the case, Ichiro secretly teams up with Shiro pretending to be lovers, as they work to deceive Ichiro's boss.
