"Congratulations on your graduation, it's been five years..." It has been five years since I started a secret relationship with my son's friend, Kitayama-kun. Five years ago, when my husband's infidelity was discovered, Kitayama-kun comforted me with a gentle kiss. I waited until his graduation ceremony so as not to interfere with his exams. Then, I responded to Kitayama-kun's feelings and had our first physical relationship. For the next five years, we continued to meet secretly behind my husband and son's backs, but our relationship changed when Kitayama-kun got a girlfriend...
