 The Demon Lord Satan seeks to conquer the world of Ente Isla by annexing its four continents with the help of his demon generals Alciel, Lucifer, Malacoda, and Adramelech.After being confronted by the hero Emilia and her companions, after they had killed Malacoda and Adramelech, Satan and Alciel escape the world of Ente Isla through a gate to modern Tokyo, Japan.However, due to the lack of magic in the modern contemporary world, both Satan and Alciel change into forms representing what they would look like if they were human.