Responses
I dont think this is it but it might be
http://www.mangago.zone/read-manga/raise_wa_tanin_ga_ii/
http://www.mangago.zone/read-manga/ojou_to_banken_kun/
but you should definitely read raise wa tanin ga ii tho (≧∀≦)
Its a manga about a girl that has a yakuza grandpa and lives with the yakuza. She loves this one guys thats like 10 years older. And that guy is like veryyy overprotective and nice.