Yakuza: Black Panther is a Manga/Manhwa/Manhua in english language, ACTION series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

Tatsuya Ukyo is an aimless youth on the streets of Kamurocho who is framed for an assault that left a young boy comatose. He drops out of high school during his second year and lives a hoodlum's life with Tenma (his only friend) and Saeko, his sister who raised him for nine years after their mother's death. Hearing about a large sum of money held by a loan shark, Tatsuya and several other hoodlums break-in at night. Tatsuya defeats Naoki, not knowing he killed him. After Toda's death, Tatsuya receives an ultimatum from a member of his gang: win ten consecutive fights or be arrested. Tatsuya agrees, and as he fights underground he bonds with trainer Kudoh Saki and physician Amamiya Taizan. Based on the PSP game.