"Congratulations on your graduation, we're just like we were five years ago..." It's been five years since I started having a sexual relationship with my son's friend, Kitayama-kun. It all started five years ago when I found out my husband was cheating on me, and Kitayama-kun comforted me with a gentle kiss when I was feeling down. Not wanting to get in the way of their entrance exams, I waited until graduation day. Then, in response to Kitayama-kun's feelings, we had our first physical relationship. For the next five years, we continued to meet up behind my husband and son's backs, but our relationship changed when Kitayama-kun got a girlfriend...