Sailor Suit and Machine Gun: Graduation (2016)

Yakuza underboss and schoolgirl Hoshi Izumi intends to become a regular student once again following a period of unleashing bloody revenge upon those who murdered the former yakuza boss. However, the fix is in when a classmate dies in a haze of drug-related circumstances. Izumi is compelled to redraw her machine gun and train it on a cadre of unsavoury businessmen, politicians and yakuza.