Arm of Kannon

Plot
Sixteen-year-old Mao and his older sister Maya haven’t seen their father since his disappearance three years ago. One day, their father unexpectedly returns home with the Arm of Kannon, a cursed Buddhist artifact, which could bring about the end of humanity. Mao, Maya, and a mysterious swordsman that has emerged to protect them must try to stop the government from obtaining the Arm of Kannon and using it to create super-soldiers for the military.