or hate her character.
She first appears in the Mr Mercedes-Finders Keep-End of Watch trilogy, returns in The Outsiders, and then makes an appearance in a novella in the If It Bleeds collection.
While I don't think you have to have read all of them to understand the individual works, you will be spoiled to certain events in the original trilogy, and the world building is all done in the original trilogy too. The knowledge going into them enhances the book though.
I should add a disclaimer that the books do heavily feature real world politics, so if you need an escape from that, it might not be the best time for that. If that doesn't bother you, I hope you enjoy them. They're a fun ride.
Here's a link to the reading order: