Shadow walker

the long version

"Sarah Rivera has a lot going on in her life right now. It's bad enough that she's being shipped off to Temt Tchaas Academy, also known as Neteru Academy, a high school for future Guardians of the Light who have special powers, but she has to go there with her cocky twin brother and the rest of her compound brothers and sisters. To make matters worse, everyone has ridiculous expectations of her all because her parents are like supernatural rock stars for saving the planet sixteen years ago. But what nobody, not even her best girlfriend Tami seems to be getting is the fact that, she's not special, doesn't want to be a demon-hunting hero, and is even afraid of the dark!"--Author's website.