It wasn't a joke. My student, Sato-kun, who had no clear future plans and was just drifting through school, told me that he wanted to go on a date with me after graduation. I laughed it off, assuming it was just a silly remark, but from that day on, Sato-kun suddenly changed—and my heart began to waver. Just once, I thought, it wouldn't hurt, and my husband would never find out. Before I knew it, I had fulfilled the promise. After graduation, we continued our dates as agreed, but what followed was a turn of events I never expected.