I'm a librarian who loves anime, manga, and reading a wide variety of genres.
I had no idea Steam had these. Even though I've had the visual novel attention span of a goldfish lately, I decided to do a bit of shopping and picked up Higurashi (Chapter 1) at a slight discount and Amnesia: Memories at a major discount.
I know both primarily via the anime series based on them. I expect I'll enjoy Higurashi, even though I already know at least some of the plot twists. Amnesia: Memories is another matter - I'm mostly just morbidly curious about that one. Plus, it's very, very cheap right now. I'd never have bought that one at its original price. The anime included one of the most twisted "nice guy" characters I've ever seen in a series that I don't think is classified as horror.