The story centers on the four brothers of the Corsarino mafia family: oldest son Alan, second son Bellini, third son Chris, and fourth son Dino. The brothers respond to a call from their grandfather, the Don of the family, to gather at the family home. When they arrive, the siblings learn of their grandfather's death. The will says that Marika, their grandfather's fiancé, will choose the successor to receive the inheritance.
Note: The September 2019's Shonen Magazine Edge revealed that the manga was cancelled due to "various reasons".
(Source: Anime News Network)