Sister Street Fighter: Hanging by a Thread [女必殺拳　危機一発]

Koryu heads to Yokohama in search of a woman named Birei, kidnapped by diamond smugglers who move their hot rocks by surgically implanting them into the nubile buttocks of Chinese prostitutes. Koryu's older sister, working as a jewelry designer, is secretly, if unhappily, involved with the gangsters.