Demons Roots: Yakusoku Sareta Haiboku

Following the defeat of the Demon Lord, the surviving demon population retreated to the Dark Realm. A millennium later, facing imminent extinction, the demon race initiates a final invasion of the human world as a desperate measure for survival. Upon their return, they discover that the human society has fundamentally changed; rather than being united, humans have turned against one another. The impoverished and oppressed segments of this society find an unexpected alliance with the very demons who had previously terrorized them. This unlikely coalition joins forces to combat the powerful victors who currently hold all authority. Their shared objective is to secure freedom and establish a world where they can live as their own, challenging the existing power structure that has left them downtrodden.