After moving to Tokyo, I never returned to my parents' home, but it was the third anniversary of my father's death, so I decided to return for the first time in two years. Then there was a stranger sister with huge breasts. I heard that she is my brother's wife and her name is Kira. While spending my days at my parents' house, I witnessed the hot work of my brother and sister-in-law many times. On the morning of the day I returned to Tokyo, I couldn't stand it anymore, and when I confronted Kira-sister-in-law about my feelings, the answer that came back was too surprising!