The gun's mercy

Miya Atsumu together with his brother Osamu have entered the mafia group Inarizaki ever since they were young. Atsumu's life has always depended on a weapon, and now more than ever. He always has annoyed everyone around him, but this is a problem if you are a member of a mafia. Rivals are after him, since he's one of the best assasins in Japan, but luck seems to be on his side, as he always gets away, unscratched or not, but now that his life is in bigger danger than ever, the mafia boss, Kita Shinsuke, sends him together with his brother away, in Tokyo, where they meet the Black Jackals mafia group. There, everyone is more brutal than Atsumu is used to, but the worst one is Sakusa Kiyoomi, the boy he's partenered up with. Is Atsumu gonna make it alive, despite all the obstacles that appear in his way? Read the fanfic and find out. ;)