Perfect Community Rules

I inherited my aunt's apartment in the old town, and when I moved in, I realized that everything here was weird. Article 1 of the property manual: "Please make sure your neighbors are human." There is always someone knocking on the door late at night, but there is no one in the peephole. Until I found my aunt's diary under the bed. The last page said: "Don't trust anyone, including yourself. Also, never go to the 14th floor. " But my apartment is on the 14th floor.