A lover who was defiled by his father

Nagisa, who had been reluctant to date a man due to the trauma from her student days, was filled with happiness when her new boyfriend finally proposed to her. One day, I went to his parents' house to say hello for the first time... Nagisa froze when she saw the face of her father, who was a fatherless family. Her father was the principal who stole Nagisa's virginity during her high school days. Nagisa laments her fate, but her father hands her the vibrator he used at that time and orders her to use it during sex with his son tonight.