This creepy novel is awesome. It scares you enough to keep you going on, trying to figure out what the heck is happening. It's called Beyond, and was written by Graham McNamee.
Summary: "Jane is not your typical teen. She and her best friend Lexi call themselves the Creep Sisters. Only Lexi knows why Jane is different from anyone else: Her own shadow seems to pull her into near-fatal accidents. Jane is determined to find out why these terrifying things happen, and to overcome her shadow enemy. Her sleuthing with Lexi connects her own horrors to the secret history of a serial killer." (Oh, Goodreads, what would I do without your wonderfulness?)
This novel was super interesting, and picked up fast. However, there was a drag to it in the middle, and you kinda want it to go faster, to learn more earlier.
In Conclusion: It's a quick read, so why not?