When they first met, he was a substitute teacher; when they met again, he was the brother next door to her biological parents; in the end, he became her sweetheart. For Jingxi, what she thought was the first meeting was not really the first meeting. He was smarter than others when he was young, skipped grades in school, and had already finished elementary school when he was ten years old. At this time, he had just learned that Uncle Jing's family next door had a younger sister. The little sister was already one year old, because Uncle Jing and the others had placed her in a distant and remote relative's home for foster care. In those years, Jincheng was in turmoil, so he had never seen her. When he graduated from junior high school, he heard that the little sister was missing, but the Jing family did not look for her, they just called the police. When he was twenty-three years old, he heard that the little sister had been found, but she refused to return to Jincheng. It wasn't until he returned to China that he saw her again, and he met her as her teacher. Unexpectedly, the fate of the two people became entangled from then on, but in the end, he still hurt her. He was a good medicine for her nightmares and a witness to her youth. He gave her unprecedented happiness, but he was also one of the hands that pushed her into the abyss.