On a scorching summer day, I was supposed to enjoy dinner with my wife and family. While my wife went to pick up her mother, I found myself alone with my long-time crush—my wife's older sister, Ayaka Muto. I struggled to maintain self-control, but my desire for her was overwhelming. As night fell and I headed to the kitchen to prepare dinner, a sudden massive blackout struck. Trapped together unexpectedly for the night, I could no longer suppress my arousal at the sight of sweat dripping from Ayaka's body...