From Noboru Iguchi and Yoshihiro Nishimura
Rin, a bullied teenager discovers her arm has mutated into a razor-sharp weapon on her 16th birthday. A shadow government organization immediately begins hunting her down, slaughtering her parents in the process, but Rin is saved in the nick of time by a super-powered being called ‘Hiruko’. Soon, mutants from all over Japan are gathered together and begin militant training to overthrow the government. Meanwhile, Rin is fitted with a special iron mask and begins her life as a ‘battle girl’, utilizing both her mutant powers and acrobatic abilities to fight against mutant-hunting special forces.
Source: Nippon Cinema