The soft jazz humming through the café speakers was barely audible beneath the gentle hiss of the espresso machine. The morning rush had passed, and a tranquil lull had taken over. Katherine stood behind the counter, wiping down the bar with a fresh cloth, her apron tied snug at the waist, hair loosely pinned up. Her café—her little kingdom—smelled of vanilla, cinnamon, and ground espresso beans. But today, she was distracted.

She leaned her elbows against the countertop and unlocked her ...