Kanon had grown accustomed to living alone with her father, but her daily life takes a sudden turn when her stepbrother arrives. Her father remarries and brings his new wife and stepson into the household, forcing Kanon to live with them. Disgusted by her stepbrother's presence and repulsed by the situation, she grows increasingly irritable each day. In the midst of her rebellious phase, Kanon is caught masturbating in her room by her stepbrother, who uses the secret as leverage to blackmail her. Powerless, she is forced to submit without telling her parents, and ends up penetrated by her stepbrother's bare penis in a deeply humiliating experience. However, the overwhelming pleasure becomes impossible to resist, driving her into intense orgasms. Yielding to his control, she obediently submits to him, enduring three full days of creampie after creampie.