Two years after the death of the devil king, the Netherworld became embroiled in chaos, full of devils that had designs on the throne of the devil king. Just woken from a deep slumber, Laharl did not even know of his father’s death, and had to join in the battle for the throne with his numerous subordinates.
Amongst them, there was the angel-in-training Flonne who once had her mind on assassinating the devil king, but was now exploring the devil nature and thus tagged along with Laharl, as well as the servant of the dead king, Etna, who seemed to have her own motives. The struggle to become the rightful successor to the throne started to expand from the Netherworld.