Madame Marciano (マルチアーノ Maruchiâno?) Voiced by: Yoko Sōmi (Japanese), Kira Vincent-Davis (English) Madame Marciano is a high-ranking official of the Syndicate "Guild" that operates above the law which she broke off from to form another syndicate named "Criminal Guild" not soon after the story started when her motives were questioned by "Guild" members. Untouched by investigators, she commands the 12 Sisters, a squad of hitwomen made up of her robotic "daughters." Marciano is a cold woman that does not seem to care for the Sisters' well-being. She is also the one responsible for the death of the "pirate king" Bruce 3 years before the story took place.

It is revealed in the last episode that Marciano is a cyborg and lost her ability to bear children because of this, which led to Nielsen's creation of the 12 Sisters. She seems to have had past relations with the Pirate King Bruce Dochley, or at least might regret having him killed, despite her denying this. She despises the coyotes, believing that they robbed her of her dreams.