Yoko; a cyborg from the planet mars was sent on a suicide mission to earths orbital ring to upload a virus that disrupted the navigational systems of the attacking Levathan ships. She was captured shortly afterwards by an operative of the Merovingian, Caerula Sanguis. Regardless, Yoko was still sent to the surface.
After being destroyed, Yoko's damaged head and torso are found by Machine scientist Daisuke Ido while he searches the scrapyard for parts to use in his cyborg repairs.
Ido decides to fully rebuild her, and name her after his cat, Gally.
Gallys memories are wiped although flashbacks of her past resurface in the forms of dreams.
When the reanimated Gally suspects Ido of murdering women to provide her body parts, her guilt causes her to track and confront Ido. She discovers that he is a hunter-warrior, or bounty hunter, and that he is seeking the true killer himself.
Her fight to protect Ido causes an instinctive recollection of the lost Martian Martial Art technique called Panzer Kunst, as she quickly applies a single killing blow to the murderer. She decides to become a hunter-warrior herself
......... in which job Gally occasionally displays a disturbing bloodlust and love of battle.
Gallys first battle as a hunter-warrior is against a gigantic, body-snaching, brain-eating cyborg monster named Makaku, who destroys the original body that Ido had made for her.
Ido rescues her, while almost dying in the process, and feeling he has no other choise, reconnects her head to an ancient cyborg body called a berserker body, which had been especally made for war.
Equipped with a new, stronger body, Gally is once again challenged by Makaku, who has become obsessed with Gally. After a long fight in the sewers underneath the Scrapyard, Gally kills Makaku.
Gallys drive and skill makes her the best hunter-warrior the Megacity has seen. Her skill and reputation as a hunter-warrior and motorball player elicit interest from Tiphares, the elite Machine society suspended over Megacity to which she harbors some hostility.
Eventually, after a confrontation with a resurrected and enhanced rival, Gally is forced to become an agent for Tiphares.
Despite this ironic twist of fate, Gally thinks of herself as a possible bridge between the utopian Tiphares and impoverished zionites of Megacity.
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(interpolated from wikipedia)