Within the Social Welfare Agency, a group of young girls undergoes a haunting transformation, rebuilt with cybernetic enhancements and taught the art of assassination. Among them is Triela, the eldest, who hunts her prey with unyielding determination for total destruction. Her adversary, Pinocchio, a former boy molded into a lethal operative by the terrorist group FRF, mirrors her intensity with his cold efficiency in combat. Stripped of their humanity, these once-human beings now exist as remorseless killers, driven by fragmented memories of their past selves and a ruthless urge to emerge as the ultimate survivor in this deadly game.