Live Machine

Reiji Ariyama is a skilled jazz pianist who performs at a nightclub in Roppongi. Behind the scenes, he is an assassin with the code name “Live Machine." Reiji's skills and experience as a mercenary were honed on the battlefields of Africa and his qualities as a killer are recognized by A Chinese man who calls himself “Q,” who recruited Reiji to become a hit man. Whenever Q asks him to do so, he can take out big names in the political and business world. However, unbeknownst to Q, the men Reiji killed were all members of a secret organization called the “Yumi Arc Association." Realizing that they are being targeted by someone, they hire radical terrorists and order them to search and destroy the mysterious assassin... A masterpiece of hard-boiled action!

(Source: Group Zero, translated)