“Both of them?” I whispered to myself, the question hanging in the stale air. Exhaustion finally won—I splashed my face with a handful of cold water from the basin and collapsed onto the narrow cot in the corner, too drained to bother with Bianca’s neatly arranged vials of painkillers.

Dawn arrived not with silence, but with the shrill chatter of sparrows crowding the windowsill. Sunlight stabbed through the grimy glass, and the distant rush of the river below yanked me fully awake. My throat burned. The medicine. Bianca would skin me alive if she discovered I’d ignored her instructions again.

The bathroom door creaked open. A shadow fell across the...