A bounty hunter named Roy hunts down a felon, while the green-haired, caped person is chased by two girls in super special outfits. The girls try to fight, but the green haired figure simply swats them away before fleeing the scene.
The next day, Roy returns to the office to collect his paycheck, having successfully beaten the man to the point that he needed medical attention even after he surrendered. After collecting his fee and leaving, Roy has a flashback to the time where a giant explosion (the "Blast Fall") leveled the town, and all he found of his daughter was her shoe, turning him into the cynical alcoholic and abusive bounty hunter he is today.
The felon's brother with a gun attached to his arm and an extendable claw attached to the other tries to take revenge for what Roy did, but he is interrupted when the green-haired figure falls to the ground between them. Roy decides to take her home as an act of kindness. When she wakes up the next day, Roy tries to get rid of her, but she can't remember anything so she decides to follow Roy instead. Roy tries to shake her off, but she just keeps following him.
However, when the evil brothers managed to hijack a construction mech and kill Roy with it, the green-haired girl decides to help Roy out for saving her last night. She manages to easily destroy the mech on her own, single-handedly flinging it into the sky where some phenomenon called the "Aurora shell lightning" zaps it for breaking the altitude limit. Roy claims that the two of them are even, and briefly tells her about his daughter Rita before leaving.