Bound by fate, her husband and her distant stepson... While Riho finds happiness with her beloved, she also carries a sense of loneliness. One day, she catches her stepson Daisuke masturbating in the bathroom. Seeing his erect cock after so long stirs something within her, and she impulsively jumps out, propositioning him, "Use that cock for me!" Despite being a virgin, Daisuke's awkward breast fondling and passionate sucking on her pussy are so cute that Riho, unable to resist, accepts his throbbing cock and helps him graduate from virginity with a raw, creampie finish! Daisuke, guided step-by-step in the ways of sex, spends every day fucking Riho all over the house, repeating their thrilling incestuous acts. Eventually, Riho, driven to the brink by her desire for a child, begs Daisuke for a creampie, their forbidden relationship deepening into something unyielding.