As Many Souls As Stars - Natasha Siegel

Cybil Harding is a girl born under cursed stars, destined to bring disaster to those around her. Miriam Richter is a creature born of shadow. Forged by the dark arts, she is doomed to exist for eternity and destined to be alone.

Everything changes when Miriam encounters Cybil, whose soul shines with a light so bright, she must consume it. Entranced, Miriam offers a bargain: she will grant Cybil reincarnation and the chance to change her stars in exchange for her soul. Thus begins a dance across centuries as Miriam hunts Cybil in every lifetime to claim her prize.

But as the two women circle each other in their battle for dominance, the bond forged between them grows stronger.