My childhood friend Kayo got married. It was only then that I realized I was in love with her, and secretly regretted it when I married my current wife. Some time later, Kayo returned to her parents' house. The feelings deep inside my Kokoro flared up again when we met again... and I ended up forcing her down on me. Sex with Kayo felt amazing, but I felt deep regret as she left. But I couldn't turn back now, so I approached Kayo again...