New York's underground sewage system was a complicated project because it was rebuilt and modified in every period of history.
As time went on, even the most recent construction workers didn't know how it would develop.
There were even rumors that evil things lived inside the sewers.
Of course, this funny talk was at most just spread on the internet.
No one would actually believe these things.
However, there were indeed unknown forces hidden at some intersections of the sewage system.
For example, the Evil Spirit Society. It was probably one of New York City's oldest forces.
As the name implied, practically every member of the organization was an evil spirit.
It was hard to imagine that a group of evil spirits could form such a strong underground group.
Of course, there were also a few human members.
These were the evilest group of humans.