"Congratulations on your graduation..." I sent the same words to my son's friend, Hajime, as I had five years ago. On the day I found out about my husband's affair, it was Hajime who comforted me with an awkward kiss. On graduation day, filled with conflict and guilt, I responded to Hajime's feelings and had sex for the first time. From then on, we continued our sex friend relationship, hiding it from my husband and son. However, five years later, Hajime got a girlfriend, and I was forced to decide whether to continue our sex friend relationship...