Project Echo, People Who Don't Exist

On the third day after I transferred to another school, I saw the "non-existent person". It was half past five in the afternoon, the school bell had just rung, and the corridor was crowded with people rushing to the stairs. I was standing at the back door of the classroom, lowering my head to tie my shoes, when out of the corner of my eye I caught a glimpse of a person standing by the window of the empty classroom opposite. Wearing a white school uniform, with long hair covering her face, she remained motionless. When I looked up again, it was empty. I thought it was dazzling, until the next day during lunch break, I saw her again on the second floor of the old teaching building - the same standing posture, the same profile shadow, like a photo pasted on the glass. This time I didn't blink. She slowly raised her head, and I could see her face clearly from a distance of more than ten meters. Then I froze in place. That's my sister. ——Lin Zhiwei, who disappeared three years ago and was declared "possibly dead" by the police.