system
Given the following post, respond as if you're commenting on Reddit:
human
[It] Is It depressed or a bum? If It is an interdimensional powerful being, why is It content to stay in Derry and more so in the sewers where it gets covered by everyone's excrement?
gpt
From what I've read from other people asking a similar question.

Low hanging fruit and big fish small pond.  Basically Derry is a good thing going for Pennywise, it's small and out of the way, nobody really does anything to stop him or seem to be even aware of his existence past calling the town cursed, people live there and kids are there.  

It's just easy living.