Mafia is headquartered in America where assassinations are a regular happening on the roads. Inferno, a mysterious organization, is behind the majority of these dealings through using these near-invincible human weapon,"Phantom." A tourist witnesses the most up-to-date murder of Phantom 1 day. Agree to flee, the tourist hides in a building. But, Phantom, shown to be a new woman called Ein, and the leader of Inferno"Scythe Master" catches the tourist and brainwashes him. Given the name"Zwei," this peaceful tourist is currently a puppet of Inferno with no memories. Drawn into a world of lies, deceit, and violence, even Zwei must struggle to live, hopefully to a day regain his memories and escape in this universe at which he could be constantly on the verge of death.