Hei plays a gentle-hearted student from China named Lee Shenshun but when "working" he takes on the role of a seemingly (at first) apathetic and guiltless killer known also as The Black Reaper. Part of an organization of unknown ambitions known only as the Syndicate. Hei's contract allows him to generate electricity, and he is hotly pursued by the Japanese government for his involvement in multiple assassinations. He acts as the spy/assassin of his team.

Ophelia was ranked #4 in her time and widely known among her fellow warriors as a sadistic and sociopathic warrior. Despite the law among warriors that killing humans is strictly forbidden under pain of death, it is hinted that she murdered humans to sate her bloodlust. Her crimes remain undiscovered or unproven. Her self-invented nickname is "Rippling Ophelia", after her trademark sword movement. though in the anime version she used the title "Ophelia of the Ripples"