SDMF-049 — My Sister Will Forget By Tomorrow That I Have Bondage Sex With Her Every Night. Yura Tsumugi

I have a secret that I can't tell anyone. I keep having sex with my sister, whose memory resets when she sleeps after the shock of a certain incident. At first, I wanted to help her somehow by using shock therapy... But the more I continue, the more my heart feels fulfilled... Yura has become a convenient sister for me... I'm sorry I'm such a brother... I don't understand either...