Mio Mukaino

A son quits his job and is persuaded by his father to head off to a cottage in the remote mountains. Together, the two of them manage to get through their days while wearing old jerseys left by a deceased grandmother. The following summer, the two once again leave the stifling heat of Tokyo, as if escaping to the mountain cottage. However, the next summer is very different.

Tokyo is a dark technopolis, a city of faceless chrome and cold marble. It is ruled by Nogi, a yakuza boss specializing in drugs and murder. He gained absolute power by executing the former boss and marrying his daughter, Chiaki. Only the mysterious Ikko, Chiaki's half-sister threatens him. Inspired by a legendary hit-woman, Ikko calls herself the Black Angel and plans to wash away her father's murderer with a deluge of blood.