I think I'll re read it and write down all the yakuza groups and sketch my personal conceptual map of this story ><. I love this manga and i want to understand it 100%.
I found this one..the first reply talks in depth about the yakuza from the first arc there is another good explanation out there too, I'll let you know if I find it
http://www.mangago.zone/home/mangatopic/3347853/
You know guys there's this link in mangago called ''edit'' so you can unsuscribe to new updates of this manga if you hate the characters so much. Seriously, this second couple will finally confess some day but the characters will remain intact in personality because guess what!! They fell in love with each other for who they are.
So if you don't like the typical tsundere of Kenji or the obsessive fanboy personality of Yoshi then this manga is not for you anymore.
Don't expect to always get what you consider correct behaviour in a work of fiction that depends of non perfect characters to have a plot and development.
Bye Dean! Bye uploader!! (;_;)/~~~