When I was young, my mother left home for another man. My father cried every night, which made me very sad. However, I still behaved normally at school so that no one would find out about my family's situation. A few years later, my father remarried, and I gained a new family - a kind and gentle stepmother, and a slightly game-obsessed older sister. I truly felt incredibly happy. A few years later, I left my hometown to study at a university in Tokyo. It was my first time living alone, so my father was very worried, but he was also very proud of me. My mother felt the same way, and that made me the happiest. But just a few years later, my father passed away. Today is his birthday, so I returned to my hometown. Nothing has changed here. Seeing my mother healthy, I feel extremely happy. My step-sister hasn't changed at all, still messy, in her 30s, lonely, wearing sloppy clothes, addicted to games, not wearing a bra, wearing socks like an old man... In fact, there used to be some wrong emotions in my mind. And to cut off those feelings, I chose to go to Tokyo. But upon returning, meeting my step-sister again, those emotions resurfaced. When I unexpectedly saw her masturbating in her room, I couldn't bear it anymore! And after that incident, I also realized that she seemed to have feelings for me, a very wrong kind of feelings. A few days later, I returned to Tokyo, promising to come back here next year, to see her again, and perhaps the child that she had already named for us...