Queen of Dreams by Kit Rocha

Three lovers with unbridled hope, uncanny dreams, and ancient powers join forces against the greatest evil in the world in a scorching fantasy by the authors of Consort of Fire.

Ash waited three thousand years for a consort who could break the Betrayer’s chains. Instead of one lover, he found two: Sachi and Zanya—the primordial powers that embody creation and destruction, reborn as humans. Now, his ancient enemy has returned to threaten everything he loves.
In the wake of her dazzling manifestation, Zanya seethes with magic and restless energy. Her command of the Endless Void will be a potent weapon in the coming war. To harness it, she’ll need to embrace the darkness within—but the scars of the past are holding her back.
Sachi’s unprecedented connection to the Dream deepens, leading her beyond the veil of reality…and into the heart of the Betrayer’s stronghold. Torn from her lovers, Sachi must use all her wit and cunning to survive the Betrayer’s treacherous court. Because he doesn’t simply want her. He covets the slumbering power she possesses—and plans to take it for his own.
Even if it ends their world.