Mafia bl recommendations

Mayday mayday mayday
When the yakuza falls in love
Our companionship

I also prefer colored ones

Twittering Birds. I mean, if you haven't already.

Shutline
Legs that won't walk
Mad Dog
Dangerous Convenience Store
Wet Sand
Hyanghyeon Text
Papa Wolf and the Puppy (the cutest of all)

Manga :
Canis (stellar art)
Honto Yajuu
Tight Rope
Acid Town

Non-BL (give it a try) :
Raise wa Tanin ga Ii

Personal favourite (cuz funniest) :
Gokushufudou: The Way of the House Husband

Viper
Golden Opportunity
Can a Gangster Leave the Gang?
Low Tide in Twilight
Max Mojave Case Files
Cover Up

Manga :
Monetary Love
Interi Yakuza wa Daite Aishite, Hanasanai!
Groping in the Dark
The Omega Takes a Husband
Tasuketa Yakuza ni Nerawaretemasu
Kozure Omega to Boukun Yakuza
Witch and Cat
A Kiss for Each Face
Syunrai to Mitsu
Hakujin to Kurobotan