Yuu was a classmate of my older brother and an upperclassman during my school days. Unlike my brother, she was kind to me, a shy and unremarkable guy, and I harbored a one-sided crush on her for years. I never imagined she would end up marrying my brother, and the news shocked me deeply. While searching for a job, I started living with my brother and his wife, spending each day overwhelmed with complicated emotions. I had kept a love letter I wrote to Yuu back then—never having given it to her, yet unable to throw it away. When she discovered and read that letter, my long-held feelings suddenly began turning into reality. Before long, Yuu and I were having creampie sex again and again.