Mafia GL?

https://www.mangago.zone/read-manga/yakuza_yuri/
^Has a pretty big age gap(High schooler x adult)
https://www.mangago.zone/read-manga/my_love_is_a_gangster/
^Half of it is SL
https://www.mangago.zone/read-manga/gwanggong_industrial_complex_barrel/
^Sorta? FL is the daughter of a shady businessman
If you're fine with thieves instead of mafia, there's also this:
https://www.mangago.zone/read-manga/long_night_come/
That's all I got, sorry. It's not a very popular GL trope.

Thanks!