A Sword in the Ember by Chloe C. Penaranda

Here is a summary with spoilers of A Sword in the Ember

Faythe, now struggling with her newfound Fae identity, finds herself caught in a whirlwind of change and uncertainty. She was dead for 13 minutes, or so Rhy tells her, but against all odds, she’s alive—and now Fae. The transformation is both confusing and daunting, and Faythe grapples with accepting this new part of herself.

A plan is set into motion: Faythe will finish her quest, while Rhy will pretend she’s still dead and return to her father. They are separated for a while, but when they finally reunite, they set their sights on her kingdom, Rhyenelle.

Upon returning to Rhyenelle, Faythe’s presence stirs up tension, particularly from her rival for the throne. Now, she must face the pressures of the court, testing her strength and cunning as she deals with her scheming cousin. Amidst political intrigue, Faythe plays the court games: battling those who claim she isn’t the rightful heir, pretending to court other potential suitors, and continuing her preparations for the war against the dark fae.

Throughout all of this, she and Rhy are forced to stay apart, a painful separation that tests their bond. Meanwhile, the story introduces Kyleer, a general and close friend of Rhy. Kyleer has the power to shadow teleport and is caught up in a forbidden romance with Zaiana, a dark fae who has a troubled history with Faythe.

The book reaches its climax as the dark fae infiltrate Rhyenelle. Rueban reveals his true allegiance, and King Agalhor, Faythe’s father, is killed. The dark fae capture Rhy, and in his final moments, he orders Kyleer to take Faythe away. The book ends with this chilling turn of events, leaving Faythe’s fate uncertain.