Childhood friends and close companions, Mayu and Yuzuka, decided to hike down a mountain trail on their way back from a short trip, but soon got lost. Exhausted and helpless, they were "rescued" by Taichi, a man living in a mountain lodge. Taichi resided there with his father and used the lodge as a hideout to capture women and subject them to repeated sexual assaults. Unable to resist, he overpowered the two girls and raped them repeatedly without contraception. When local yakuza members learned of his actions, they joined in the abuse. Gradually, the girls were psychologically broken, lost their sense of self, and ultimately descended into a life of sexual slavery.