Synopsis
In the city-state of Cremona, a mysterious vigilante known as "Killer B" is on the loose. Armed with a blade and unnatural abilities, he dispenses his own form of justice, attracting both admiration and hostility. Failing to apprehend this outlaw, the Royal Investigation Service (RIS) brings in Keith Flick—a gifted but unconventional detective who was reassigned to the Archives Department following a personal loss. As the crimes escalate from quiet executions of criminals to elaborate assaults on high-profile targets, it becomes clear that more than one person is behind them. With the help of his impulsive partner Lily Hoshina and even Killer B himself, Keith uncovers a web of conspiracies involving secret organizations, domestic terrorism, and unethical human experiments. As the RIS exceeds its authority, the true extent of governmental corruption and the loyalty of those closest to him come under scrutiny.