A story about a mafia family. They are a wealthy family. Everyone respects them because they are very powerful. In a mafia family there is a mafia king and a mafia queen. They are among the most feared people by everyone. They also have 3 children. A girl and 2 boys. They are nicknamed the 'Watanabe Siblings'. They are the most important people in the mafia world. They are a genius and agile. Everyone wants people like them in the world of business or mafia. They get a lot of requests from all kinds of people. But they rejected all the requests. Mafia king and mafia queen or their parents train them a lot about the mafia world. They have killed many people who disobeyed their orders. And since then they have been feared by everyone.