Mortal Principle

At 2 a.m., a black mass grew in the corner of the second floor of Jiangcheng University Library. It moved, deformed, as if learning to stand. Shen Zhuo, a maintenance worker, crouched nearby, watched for a while, then filled out a repair form for 'pipe leakage' and stuck it on the wall. The mass thinned from the edges, leaving only a patch of wall slightly lighter than the rest. He doesn't exorcise or fight; he just turns the inexplicable into paperwork using forms and regulations. Things that are classified become quiet. He calls this 'Mortal Principle.' Until a line of pencil writing appeared on the back of the repair form: 'Teach me.' The same handwriting appeared under the red-inked 'Observer determines reality' on page 137 of the library's blue book. Meanwhile, physics junior Li Zheng was experiencing her 18,000th sleepless night—every day at 3 a.m., her right wrist burned on schedule. Three hospital visits, all normal. There's an abandoned gray building south of the city, its west window on the third floor lighting up at 7 p.m. every night. Shen Zhuo went three times; each time the light went out as he reached the building. But Li Zheng can enter, because the mark on her wrist is connected to an agreement expired 14 years ago under the gray building. Inside that window stands a figure. Through the dusty glass, it waits for her. — Description from novelcodex.org