Riho Matsumoto, a stepbrother who had sex with her busty aunt who had returned to her hometown to help with household chores while his wife was pregnant (JYMA-054).

Three years into our marriage, my wife became pregnant. She said she wanted to give birth back in her hometown, so she went back. I resumed my single life after a long time, but my wife's younger sister came to help me with the housework. My stepsister, whom I hadn't seen in so long, had grown up; she was beautiful and charming. Although I knew it wasn't right, I still treated her like a woman. When it was just the two of us at home, I couldn't calm down. Just then, I saw my stepsister masturbating, and unable to resist, I moved closer to her…