All the fragile hearts / M. T. Solomon.

Cecelia feels like a stranger in her father's court. Her mother's identity has always been a mystery, though rumors tell of a woman washed up from the sea. A vision of her father's sends her to the kingdom of Korith, where she hopes to find answers. But sometimes a search for answers takes one down dangerous paths. Viktor might be King Ramiro's favorite Kingsguard, but that doesn't mean he can't be used as a pawn. Once satisfied with hiding in his armor, drinking, and fighting, Viktor is forced to guard the king's revered guest. And then he's forced to marry her. But Viktor doesn't believe in love. Not after growing up in the hostile House of Black where his volatile father railed and his delusional mother ignored his pain. But that doesn't explain the guilt he feels when he betrays his new wife. As whispers of a rebellion spread and a political coup takes shape, the sudden murder of the king plunges the kingdom into chaos. Separated from each other, loyalties are tested and sacrifices made as Cecelia and Viktor navigate a perilous web of intrigue and lies, leaving them to discover how strong their fragile hearts really are.