I honestly didn't read much as a kid. I enjoyed Judy Blume books and still like that kind of hyper-realistic fiction. I was into R.L. Stein when those were popular and still love trashy suspense.

I think the first "classics" that floored me were the macabre short stories we read in 7th grade. The Lottery, Occurrence At Owl Creek Bridge, The Tell-Tale Heart, The Most Dangerous Game, The Yellow Wallpaper, etc. I still love suspenseful, grotesque stories, especially with unreliable narrators. Chuck Palahniuk is my favorite modern novelist of that genre. His book Diary is the only book I've ever had to put in the freezer because it unsettled me so badly lol.