Kentaro Yabuki Black Cat Vol. 1

Black Cat is the code name of former Chronos assassin Train Heartnet who now works as a bounty hunter or “sweeper” alongside his partner Sven Vollfied. Train may think his dark days are all behind him, but will he ever be able to escape from Chronos' watchful eyes? Find out in this hit manga series from Kentaro Yabuki!
In volume 1 of the Japanese language manga, Train and Sven go after a weapons smuggler selling dangerous tech on the black market and make a new acquaintance in the process, but can they really trust their new friend?