There are things that upset us. That's not quite what we're talking about here, though. I'm thinking rather about those images or words or ideas that drop like trapdoors beneath us, throwing us out of our safe, sane world into a place much more dark and less welcoming. Our hearts skip a ratatat drumbeat in our chests, and we fight for breath. Blood retreats from our faces and our fingers, leaving us pale and gasping and shocked.
- From Trigger Warning: Short Fiction and Disturbances by Neil Gaiman