Miru, a bright and lively female college student, and Shion, her quiet and gentle schoolgirl sister, were renowned as the beautiful sisters in their neighborhood. Their mother, who had lost her husband early, remarried, and they gained a new stepfather. Then, their mother became pregnant and decided to give birth at her parental home for safety reasons. After their mother left, their stepfather changed drastically, starting to look at the sisters with lecherous eyes... 'Without your mother, you two sisters are just ordinary women...' Miru and Shion were brainwashed and trapped by their stepfather's insatiable penis.
