People Walking on the Border of the World

In the vast rainy nights, there are always a group of people holding black umbrellas and wearing silver rings appearing in every corner of the city. According to insiders, these people sometimes appear in their own yards, sometimes in their rooms, sometimes in the streets and alleys, and sometimes in the city's sewers. But without exception, whenever anyone sees them, they disappear without a trace. This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.