Madame Marciano (マルチアーノ Maruchiâno?) 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 a squad of hitwomen made up of her robotic "daughters" called the 12 Sisters.
Marciano is a cold woman that does not seem to care for the Sisters' well-being and she is also the one responsible for the death of the "pirate king" Bruce Dochley 3 years before the story took place.
In the last episode, it is revealed that Madame Marciano is a cyborg who 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 as she believes that they robbed her of her dreams.
- Madame Marciano is seen dressing masculine and feminine.