Dantalion and Sytry must return to the netherworld when the four Kings of Hell come together for their annual summit.  None among the crowd realize that the Grand Duke Baalberith has secretly sent a horde of demons to the human world to kill William, the Elector who inherited King Solomon's soul.
What happened to the so-called 
power struggle in Hell, anyway?
¿Y qué rayos ha pasado con su 
lucha por el poder del infierno?
¿Y qué rayos ha pasado con vuestra 
lucha por el poder del infierno?
E esses dois? Foi-se a 
guerra de poder no Inferno?!