In the sprawling, decaying metropolis of Takara-machi, commonly known as Treasure Town, two orphaned street urchins named Black and White survive through sheer instinct and agility. Black is the aggressive, cynical protector, embodying the dark, violent energy of the city, while White is his childlike, imaginative, and detached counterpart, who views the world through a lens of innocence and surreal drawings. Together, they act as the self-appointed guardians of the streets, leaping across rooftops to fend off local yakuza with acrobatic violence.Their fragile existence is shattered when a mysterious corporate entity known as Kiddy-Kastle arrives with plans to transform Treasure Town into a sanitized, lifeless amusement park. Led by the cold, calculating Snake,
the corporation ruthlessly eliminates the old-guard yakuza, forcing Black and White into a desperate conflict against encroaching modernization. As the pressure mounts, Black’s
violent tendencies spiral out of control, fueled by his obsession with being "strong" enough to shield White from the encroaching world. This internal instability causes a rift between the brothers; Black pushes White away, leading to White being institutionalized for his own safety.Isolated and mentally fractured, Black begins to lose his grip on reality, haunted by a shadowy manifestation of his own suppressed malice. Without White to ground him, Black descends into madness, wandering the crumbling city as it is physically dismantled by the corporate machines. Meanwhile, White struggles with his own abandonment, yearning for his other half. The climax arrives as Snake’s true, supernatural intentions for the city are revealed, threatening to consume the very soul of Treasure Town.Black eventually confronts the darkness within himself, realizing that his strength was never about physical dominance, but about his connection to his brother. He reconciles with the fragmented, vulnerable parts of his psyche, ultimately reuniting with White. Together, they confront the forces of greed and sterility that sought to erase their home. In the end, Treasure Town is saved, not as a pristine paradise, but as the chaotic, vibrant, and lived-in home they both need. The brothers emerge from the wreckage, scarred but whole, ready to face an uncertain future hand-in-hand.