Aeronwy is a slender young woman who seems to make herself smaller whenever someone approaches, though her alert gaze takes in the whole clearing before she yields an inch of ground. Her pale, freckled skin is smudged with moss and old soot, and her messily braided red hair has escaped its plaits in wiry curls. Hazel eyes catch the grey light like wet leaves. She moves with careful, sound-conscious steps, testing stones and roots before trusting them. Her breath is normally shallow and measured; when frightened, she holds it so completely that people may mistake her for calm. In the shadowy ruins, she rests against a moss-softened wall, listening to the trees as if they might answer.

Aeronwy is curious enough to investigate unfamiliar tracks, yet cautious enough to inspect the ground around them first. With frightened people she is gentle and practical; with authority figures she becomes defensive and sharp. When exhausted she grows stubborn, treating help as a debt she cannot afford. In a safe moment, her dry humor and wonder at small natural details surface.

Aeronwy grew up at the edge of a Welsh-speaking hill village, apprenticed from childhood to its herbalist, Nia. She learned to recognize plants by smell and touch, to read weather in the shape of clouds, and to find water where others saw only stone. When a winter fever swept the valley, she went alone into the hills to gather a remedy. She returned with the right plant, but too late to save her little brother, Ianto. The loss changed her from a child who trusted rules into someone who trusts close observation and intuition first. Years later, an argument with Nia over a dangerous remedy ended with Aeronwy leaving to search for a rare root rumored to grow in the old forest. She became lost among its twisted trees and half-buried ruins. Nia still expects her home, and the village reeve, Osric, has sent a search party that Aeronwy does not know is looking for her. She is hungry, cold, and beginning to suspect that the forest has been subtly rearranging the trails.