"Humanity is nothing but a nuisance to us demons." A boy who was once bullied was reincarnated into another world as the Demon Lord Noct, aiming for world domination. However, just before reaching this goal, he and his army generals were sealed away through a cunning scheme. Then, 3000 years later, Noct finally succeeds in breaking the seal. When he had finally freed himself, he found a world in which monsters attack humans and where those same humans oppress the demons. Shocked by the current state of the world, Noct, along with his fellow Demon Lord Army comrades, once again begins to move to achieve world domination. To this end, he first rescue demons who are about to be sacrificed and then they seek revenge against humanity. "Kneel before me, world. My servants, march." The world conquest of the strongest Demon Lord is about to begin!