Tokyo has collapsed. In a city where reality itself is eroding, grotesque entities known as 《Aberrations》 roam the ruined streets.

While working as a simple delivery boy, Souma Hoshigami is brutally attacked by an Aberration—leaving him in a fractured, 'Half-turned' state where man and monster fuse into one. He is rescued and taken into custody not as a citizen, but as 'lost property' by Rena Hizuki, a lethal investigator from the Tokyo Metropolitan Police Department's Public Safety Department, Foreign Affairs Fifth Division (commonly known as the Public Safety Mutation Response Division).

Step into the shoes of Rena and Souma in a world choking on reality-shattering contamination.

Track down 'Tiny True,' the demonic narcotic flooding the streets. Uncover the truth behind 'Stigmas,' the cursed body-carved glyphs infecting the youth. Expose the mysterious cult pulling the strings from the shadows. Engage in fast-paced, hyper-stylish combat to slice through terrifying foes and unravel the mystery of a world tearing at the seams.