Butterfly runs a human trafficking operation which abducts refugees so that she can harvest their organs and sell them on the black market. She classifies healthy adults as "Rank B" and children as "Rank A". When one sickly man is shown coughing, she declares him "Rank D" for "defective" and then murders him by slitting his throat with her spiked fan.
Cyborg protagonist Mylene Hoffmann murders Butterfly's criminal lover, Stinger, brings his severed arm to her as proof and then takes down the trafficking operation. The henchmen are all killed, but the villainess manages to escape. Butterfly later manages to track Mylene down after getting a tip from chief 020's Secretary (Mami Abe) who received a black eye and her glasses broken after calling the cyborg heroine "Monster".
Mylene and Butterfly have a final duel - much of which takes place in a swimming pool. Butterfly gloats that now Mylene knows what it is like to lose a close friend; a reference to a refugee named Chris whose corpse the heroine had found earlier. Taking advantage of Mylene's stunned expression, Butterfly gains the upperhand but is ultimately shot and killed by the heroine's friend, Cherise.