In this brand-new spinoff of the runaway hit series, Iruma is a dirt-poor but unfailingly cheerful young boy who grows up in a ruthless city slum. One day, Iruma gives an injured old man his last loaf of bread and nurses the stranger back to health—only to find out that the elder gent is none other than Don Sullivan, head of the Babyl Mafia! Soon after, Don Sullivan comes back, whisks Iruma away, and begs the boy to become his grandson. And just like that, Iruma begins his new life as the next in line to lead a gigantic gang of—dare we say—demonic mafiosos!