Confinement Escape: Disgraced Young Ladies (1996)

Mio and Maki are sisters who, after losing their parents, inherit a vast fortune and begin living alone in a mansion. Two men and a lawyer approach them with hidden motives, aiming to take both their wealth and their bodies. The men confine them, restrain them, and subject them to abuse as they search for the official seal required to access the inheritance. Is there no hope left for them to resist?