"The people in the trees" lives in my head rent free, but not 100% in a good way. Huge SA trigger warning (not pervasive in terms of time spent on the topic, but yeah, if you are AT ALL squeamish about that sort of thing, give this one a pass). But it is quite unlike anything else I've read and stuck with me in a way other books I randomly grabbed at the library with no context generally do not. Left me very much questioning how I view people and the world and how easy it is to allow monsters to hide in plain sight.