Erika Kitagawa and Yuka Minase play sisters whose father, once the CEO of a major corporation, disappeared after the company's financial collapse, leaving his daughters to face debt collectors. The sisters flee to their grandmother's vacant house, but are betrayed by a servant who ties them up and subjects them to forced punishment. The beautiful, big-breasted sisters are violated by men, their large breasts tightly bound with ropes. Unable to endure the torment, the sisters gradually succumb to pleasure and fall into depravity.