I still cannot forget it. The infuriating incident happened in the spring of my third year of marriage to Sana. Bored with life as a housewife, she said she wanted to learn computer skills so she could find a job. By chance, my best friend Yoshida offered to teach her, and Sana began visiting his home for lessons. Her behavior grew stranger by the day. Anxious and suspicious, I finally sneaked into Yoshida's house—and witnessed something unthinkable...