When the anime adaptation of Gansta came out it managed to gather a large fanbase but unfortunately it only had 12 episodes. The Manga version of Gangsta only had 42 chapters and left off with a cliffhanger in the middle of a major event and to make things worse the manga proceeded to go on a two year hiatus. Luckily the manga is officially coming back and the latest chapter will be released on May 20th and will appear in Monthly Comic @ Bunch. If you want to check out the manga legally then you should know that Monthly Comic @ Bunch is letting people read all the chapters for free on it’s site from May 18th through the 24th so you should check it out I guarantee that you won’t be disappointed.

Source: Crunchyroll