The protagonist and his twin sister lived in an orphanage since childhood. The protagonist was adopted by a woman when he was six years old. Because the woman knew that she would pass away soon, the purpose of adopting him was just to find a partner for her son. After the woman died, the protagonist and his brother were taken back home by the woman's mother. It was a dull and severe home, and it was for this reason that the woman left it when she was young. The woman's mother has always felt guilty about her daughter, and for some other reasons, she decided to raise the protagonist as a girl. When he was seventeen years old, the protagonist and his brother chose to run away from home because they couldn't bear it. After the two lived in a monastery for six months, their brother suddenly left. The protagonist's heart and everything were broken by his brother's departure and the despair of life. . .