Golden Blood, Rusted Feathers

In near-future Tokyo, humanity discovers fragments of the "Reincarnation Art" (inspired by "Shin Megami Tensei" and "Makai Tensho") and tries to break through the boundary between life and death through gene editing (Chimeras), mechanical modification (Onihei Soldiers), and soul sacrifice (the secret arts of Shuten Doji). But this blasphemy triggers a "Leak Between Realms":

- The "Seraphim of the Sacred Mark" from Heaven fall into depravity because of human greed (following the fallen-angel premise of "Angel Sanctuary"), becoming killers with thorn-covered wings growing from their backs;

- The "Bone-Prison Demons" of the underworld crawl through the energy fissures left by the Reincarnation Art, using living humans as "reincarnation vessels";

- Human-made Chimeras (stitched-together blends of beast, human, and machine) and Onihei Soldiers ("living weapons" modified into cyborgs) have their souls torn apart and begin indiscriminately devouring flesh.

The last balance is maintained by two kinds of "enforcers of the rules":

- Dark Justiciars: They wear "judgment masks" engraved with ancient incantations and have the authority to pass judgment on "transgressors" (including fallen angels, out-of-control creations, and humans who abuse the Reincarnation Art), but each judgment erodes their own souls (a fateful curse similar to "Onikirimaru");

- Biochemical Hunters: Bounty hunters who roam the "Lockdown Zones," the ruins worst affected by the Leak Between Realms. They make their living hunting Chimeras and salvaging Onihei Soldier cores. Their weapons are often "demons' bones honed into blades" or "guns modified with angel feathers," blending the weapon designs of "Onikirimaru" with the violent aesthetic of "AD Police".