This is an urban detective short story set in a parallel world. The protagonist Yang Li is thirty-two years old and unmarried. His parents are still alive and he has two older brothers at home. When he was seven years old, he failed to take good care of his four-year-old sister due to negligence, which resulted in her unexpected death. This incident became an unforgettable knot in his heart, leaving a deep psychological shadow that he could never forgive himself for. There were already three sons in the family. The parents were very eager to have a daughter. They did not hesitate to risk breaking the law to give birth to their youngest sister. The whole family loved her dearly. After his sister passed away, Yang Li subjectively believed that his family blamed him for the tragedy, so he always felt very low self-esteem at home. Yang Li is taciturn and introverted outside, but he is willing to help others. He is extremely dedicated to his work and has excellent case-handling abilities. He has accumulated a lot of experience in handling cases in more than ten years of criminal police work and is respected in the team. He adheres to principles, is a bit stubborn, and is not good at communication, but he is considerate. Because he does not like to show off and never grabs credit, he has never been promoted in the industry for more than ten years. At the beginning of the story, Yang Li came to the old factory area to handle a case and happened to witness the sudden and unexpected death of the suspect's five-year-old daughter. Later, he discovered that there were artificial clues in the accident and immediately reported it to the homicide brigade of the Criminal Police Detachment, but no one paid attention. After Yang Li's repeated persistence, the case was filed, but the brigade still ignored it and handed the case over to Yang Li for investigation. During the investigation, Yang Li fell into a trance because the two deaths were highly similar. In dreams and hazy consciousness, the soul of his deceased sister appeared several times and provided him with ideas for solving the case. Yang Li relied on this special
