The Mist Thief (The Ever Seas Book 3) by LJ Andrews

The third in the TikTok sensation Ever Seas series! She tried to kill him, so he made her his wife. Skadi first met her husband-to-be with blades in hand on the opposite side of a battle. She lost, and he claimed his prize. To her horror, the king of the shadow elven agrees to marry her off to Jonas, a prince in the fae realms, as a way to unite their kingdoms against a shared enemy—the light elves. Skadi knows the marriage is nothing but a political game. Feelings won’t come into play. Except her new husband makes not falling in love . . . challenging. When new threats arise, Skadi must decide to either love her enemy or keep him alive by betraying him to another.