Koori Oni

The 1990s, Hokkaido—an era when a series of police scandals that will shake the entire nation begin to come to light...! In response to a spate of gun-related incidents, the National Police Agency launches a nationwide campaign to crack down on firearms. To meet the strict quotas imposed by this campaign, "fixed operations"—in which the police collude with the yakuza—become rampant. Amidst this environment stands a man known as "The Ace": Keisuke Kido. Cultivating a network of criminals as informants, he successfully seizes a volume of firearms far exceeding his assigned quotas. Then, he crosses paths with Sho Yashiki, a high-ranking executive within the Seirinkai syndicate. Aiming to land an even bigger bust, Kido sets his sights on the Kashiwagumi's weapons cache. He enlists Yashiki for an undercover operation; in exchange for Kido turning a blind eye to his drug-smuggling activities, Yashiki agrees to join forces with him. Anticipating a sweet victory, the pair embark on their covert mission—but what awaits them is something else entirely.

(Source: Shinchosha, translated)

Note: Includes two extra chapters.