Guardian of the Drowned Empire - Drowned Empire Series, #2

Now that Lyr has survived the Imperator's cruel punishment, she has only three months to prepare for the test that will decide her fate. Despite Rhyan's promise of additional training, her life has never been in more danger. Enemies known and unknown get closer every day. While the Imperator's soldiers occupy the city, the Emartis rebels grow bolder, marking Lyr as their target. Staying safe means more time under Rhyan's protection.
But the closer they become, the more their desire ignites, the harder it becomes to resist temptation. Secrets can only remain hidden for so long. Even ones Lyr bled for. As new threats arrive at the Bamarian border, Lyr delves deeper into solving the mystery of her power. But revealing these secrets and surviving the Emperor's test may cost Lyr more than she can bargain for. Loyalty will be tested.
Lines will be crossed. Ancient promises will be reforged. And most dangerous of all: as passion burns, oaths will be broken.