Welcome to the site,
@zachm!
A couple of things - first, it is often hard to sustain that creepy, edge-of-the-seat feeling throughout a novel. It’s easier, and more common to find it, I think, in short stories. But I’ll try to give a few horror novels I’ve read in the last year or two that I thought were very good (or excellent), and that had many moments of edge-of-the-seatness.
Also, age can be a factor in one’s enjoyment of a novel. I’m not sure if you and your sister are looking for coming of age horror novels, or more adult ones, but I’ll list books that might be appealing to most people. All of these should be available at Amazon (and other book sellers), and there might be the option to get a free excerpt of a book that lets you sample the novel, before buying.
Dark Harvest, by Norman Partridge
I think this might be a good bet, and it’s short, a little over 200 pages. Creepy-creepy.
The Shadow Year, by Jeffrey Ford &
Summer of Nights, by Dan Simmons
Excellent coming of age horror novels.
The Final Girl Support Group &
My Best Friend’s Exorcism, by Grady Hendrix
Amazingly entertaining horror by one of my newest favorites. Easy reading, with interesting characters.
Break the Bodies, Haunt the Bones, Micah Dean Hicks
Hip, modern horror with a really interesting, young MC. Different and excellent.
Hex, by Thomas Olde Heuvelt
Truly creepy, engrossing horror; involves a town haunted and cursed by a ghost and the townspeople's choices.
The Return, by Rachel Harrison
A solid story about possession. Worth a read.
Small Favors, by Erin A. Craig
An unusual horror, almost literary at times, and has a rural feel, but I found it really fascinating.
The Elementals, by Michael McDowell
A great haunted house novel. Really timeless and wonderful.
And actually, one short story collection. Pretty short one, though. In case you are interested in Lovecraftian horror, here is a collection set in his extended universe:
The Coming of the Old Ones, by Jeffrey Thomas. Cosmic horror that I loved; the first story (of three) is a bit slow, but the second and third are great, epic, and really capture, I think, that Lovecraft feel.
Okay, hope there's something there you and your sister enjoy! I'm sure others will be along to give suggestions shortly.
edit to add: some of these I read over a year ago, and I do not believe they contain sexual assault; I also would not want to read a story that included that (and these just weren't that type of novel, IIRC). But as with any new author you are encountering, read the book description before buying, maybe read a sample that a book seller provides, and look at some of the thoughts people post in the comments section. Many horror novels have moments where gory things happen (it's often part of the genre), but none of the novels I listed are gore-fests, or exploitative. They might be dark in places, but aren't explicitly gory, I think.
