The Crowns of Niaksia. The Singing Bird and the Stone Heart. Book One of the Duology about the Shadowborn

The Chosen One of the Sun, Misha tirelessly prayed and brought light to all those who were sought to be engulfed by the shadows. But one day, she found herself in the shadows.
The Prince of the House of Shadows forcibly turned the young priestess into a vampire, and now she awaits execution for his murder—rejected by her god Atrokxus and stripped of her magic. But in the moment when the blade is ready to cut her throat, salvation comes. Or even harsher punishment.
Azar, the illegitimate brother of the slain, saved Misha not without reason: she is needed to resurrect the god of death. Misha is destined to embark on an incredibly dangerous journey to the underworld, confront unknown monsters, battle the worst nightmares of her own past and… choose between the sun and the shadow.
In her desperate thirst for redemption, Misha promised Atrokxus to kill the god of death right after the resurrection. This means betraying Azar. However, the sun warms but also burns, and in the shadows hide treasures that Misha never hoped to find—magic, light as breath, and love, free as a bird.