Breaking Time by Sasha Alsberg

The story blends Scottish folklore, time travel, assassins, and romance. Klara meets Callum, a Scotsman who appears out of nowhere—literally from another time. She soon learns she is the last Pillar of Time, a key figure tied to ancient magic. A dark force hunts the Pillars, and Klara and Callum must work together to survive while navigating fate, danger, and growing feelings for each other.