Sena and Fukada, two sisters, have been living with their sick mother for a long time. Their lives have been very difficult, until one day their mother remarried and everything became much better. The stepfather married the weak and sick mother not out of love, but because he had long noticed the two beautiful teenage daughters. One day, when no one was at home, the stepfather took advantage of the situation and raped the older sister without mercy. Afraid that her mother and younger sister would have to live in poverty again, the older sister reluctantly allowed the stepfather to satisfy his lust, but she did not expect that the younger sister, Fukada, would also fall into the hands of the stepfather. Both beautiful sisters have become sex slaves to the perverted old man.