Don't really know any Yuri manga but I've heard that Citrus is pretty good. It's even getting its own anime series in the future. But it's not mafia themed as far as I know.
Check out my list of yuri:
http://www.mangago.zone/home/mangalist/116626/
however I recommend Pulse, Asagao to kase san, tamen de gushi, always human, my girlfriends ex boy friend, murcielago, it'd be great if you didnt exist, vengeance, and anuything by Itou hachi
What does the fox say (▰˘◡˘▰)
thank you all <3. i make sure to check them all out!
hey ヾ(❀╹◡╹)ﾉ~ can any of you guys recommend me some good yuri manga. everything is welcome but if i have a special request, then i would like to have mafia themed. if they have one of course XD.