Passione, nothing. Practically *all* of the Stand Users from Golden Wind were members of the mafia, including Diabolo.
Speedwagon was also a gang member, so that would be fun too.
Oh, and that rabbit mobster who had the ability to transform anyone he touched into a carrot from OG Dragon Ball. And Caulifa, Kale, Kefla, and their Saiyajin gang from Dragon Ball Super, I guess.