Possession - Song and Shadow, #1

Constance Jerome wants nothing more than to make it through her senior year of high school without being noticed. But when her mother drops the world's biggest bombshell, flying under the radar just isn't in the cards. It turns out Constance is a necromancer-one of the few who can travel the realms of the dead. Apparently it runs in the family. And now there's a threat coming: another necromancer with plans to disturb the living and the dead, and Constance and her mother are the only ones who can stop him.
If only they knew who he was. Or what exactly he was up to. A quiet senior year isn't an option, and Constance must race to stop a high school apocalypse before the balance between the living and the dead is overturned.