ADN-366 I have to have unprotected sex with my sister-in-law on her fertile days as a substitute for my broke and impotent brother. Akari Tsugumi.

Next week, my wife will give birth. However, in these times, it's difficult to go back to her hometown for the delivery, so we decided to stay at my sister-in-law's place nearby. My sister-in-law is kind and incredibly beautiful—almost too good for my brother. She seemed happy. But reality was different. Despite waiting, my sister-in-law couldn't have children, so she had my brother undergo a check-up, revealing azoospermia. Seeing my sister-in-law crushed by despair, I inexplicably became aroused…