There was ZERO warning this would happen, either. No "progressing in this quest will halt progress elsewhere" or anything

No. Pretty sure lore back in the beginning of the game mentions Klee's father as traveling with Alice

I'm assuming it's because it's easier to take advantage of neurodivergent people? In an alternate reality, if I weren't on medication, I could easily be manipulated into overspending and becoming financially dependent on a terrible person.

I adore T Kingfisher's Clockwork universe. How different is this book universe from that one?