Confinement Escape: Lewd Flesh Hunting (1996)

When Kozue wakes up, she finds the brutally murdered body of her boyfriend. Falsely accused of the crime, she escapes and teams up with a man to uncover the truth behind the incident. It turns out that her boyfriend had been plotting with the yakuza to steal a diamond from the world-famous jewelry designer Junko and sell it. Kozue visits Junko's mountain villa to ask for her cooperation, but Junko demands sexual favors in return, which Kozue reluctantly accepts. However, when the yakuza arrive, Junko is repeatedly assaulted. Kozue tries to flee but ends up being captured as well…