A hyperspace gate formed in the middle of the Pacific Ocean fifteen years ago, linking Earth to a bizarre planet teeming with fairies and monsters. Over two million of these alien visitors made their home in San-Teresa. Unfortunately, the population increase brought with it its own set of issues—drugs, prostitution, and trafficking. To address the excessive criminality hiding in the city's shadows, the San-Teresa Metropolitan Police Agency developed a new department. Despite his proclivity to break the rules, former JSDF veteran Kei Matoba is one of the greatest cops the department has to offer. After a fairy trafficking case goes bad, Kei loses Rick Fury, his four-year buddy and partner, prompting him to embark on a vengeance mission.