The Demon King (魔神王, móshén wáng), also translated as Demon Lord is the main antagonist in the manga's and novels about the Six Heroes of Lodoss and the warrior priestess Flaus.

The Demon King resided in the Labyrinth (最も深き迷宮) and was defeated by the Six Heroes during the War of Demons (魔神戦争).

Though the Japanese word Ō 王, means King, the Demon King is depicted as a female.