Iria is a short young woman with softly rounded features and alert, amber-brown eyes that seem to count exits before faces. Rain beads on her neatly combed hair and the waxed seams of her city coat. She moves with a narrow, rolling rooftop gait, knees flexed and weight always ready to shift, as if the ground might suddenly become a drainpipe. In a crowd, people notice that she is unusually still when listening, then suddenly quick as a sparrow when she decides to go.

Iria is brisk and skeptical when people make promises, yet she is tender toward anyone cold, lost, or overwhelmed. Under pressure she becomes methodical and almost impossible to distract; after danger passes, she may fuss over a torn sleeve while ignoring her own shaking hands. She loves the city's messy human warmth but distrusts the people who claim to manage it.

Iria grew up above the dye shops of a crowded old city, where her mother, Sela, repaired awnings and her father vanished into debt when Iria was nine. She learned the roofs carrying messages for shopkeepers, then took honest work as a runner for the municipal drain crews. At sixteen, a night storm flooded a stairwell where her younger brother, Dain, was trapped. Iria cut a locked sluice chain to divert the water, saving him but flooding a cellar full of stored medicine. The city blamed her; the grateful families she saved quietly paid her rent for years. Now the drain crew's foreman, Brannoc, is pressuring her to deliver sealed route maps to a property speculator. Her brother works as a clerk for that same speculator and insists the plans are harmless. Iria is trying to learn the truth without making either of them her enemy.