Splintered Kingdom by Gretchen Fox Powell

Splintered Kingdom is the second book in Gretchen Powell Fox’s Shattered Crown trilogy. Elyria Lightbreaker has survived the Arcane Crucible, but the scars of the trials remain, and she must reclaim the Crown of Concord before the human and fae realms are plunged back into war.

Cedric Thorne sacrificed everything to secure victory for humankind, only to find himself burdened with powers he cannot control and bound to Elyria by feelings he cannot ignore. As the fragile peace between their realms begins to splinter, both must confront dangerous truths, their growing attraction and the darkness threatening to consume them.