The entire trilogy collapses into Kei's actual powerlessness: he can't regenerate his way out of this, and neither can the audience pretend watching ajin kill each other matters anymore. Satou stops being a villain with a plan and becomes something worse, a force that destroys the world by simply existing in it. By the ending, you're not rooting for victory; you're watching two people try to survive a apocalypse they created together, and one of them has to lose.
Kei has finally cornered Satou, the terrorist ajin who has terrorized Japan with his immortal body and twisted ideology. But victory tastes hollow when Kei realizes Satou's influence runs deeper than anyone suspected. The moment seems ripe for resolution, yet the revelation of Satou's true nature shatters every assumption about what he actually is. As Kei prepares his endgame, ajin extremists emerge from the shadows with their own agenda, turning the conflict into something far more complex than a simple manhunt. The lines between hunter and hunted blur as competing factions collide, each convinced they alone understand what ajin should become. The supernatural horror that defines these immortal beings reaches its crescendo, forcing Kei to confront not just Satou's monstrosity, but the existence of ajins themselves in a world that can never know they're real. Survival and victory are no longer the same thing.