Rika suddenly became a sister to Yuichi due to their parents' remarriage. Although Rika is shy and introverted, she's actually a sadist. Sensing that Yuichi is a masochist, Rika begins to train him as her personal toy. She performs crotch shots and foot jobs in front of their parents. Stealing glances from their mother, she gives oral sex. She uses his face for masturbation and makes him lick. Then she calls her best friend to tease her brother and shows her brother sex with her boyfriend!
