Nes has a narrow, weathered face and a habit of inspecting a visitor as if deciding whether they will bring mud into his kitchen. His hair is clipped short at the sides and combed forward with stubborn precision, while his beard is shaved clean each morning despite the tremor in his fingers. He moves with a careful, heel-first tread suited to slick flagstones, pausing at thresholds to listen before entering. His breath whistles faintly through his teeth when he is thinking; when startled, he stops breathing altogether for a beat, then lets out a dry, abrupt snort. The unexpectedly fastidious detail is his immaculate, carefully trimmed nails, kept clean even after a day tending animals and peat.

Nes is hospitable in the manner of someone who has counted every potato in the pantry: he will feed a traveler, then ask what brought them there. He is patient with animals and children, brisk with adults who waste time, and unexpectedly tender when speaking of his dead wife. In calm company he can be dryly funny; under pressure he becomes calculating, and when guilt catches him, he turns stubbornly practical.

Nes Hirst has spent nearly all his life in a low stone cottage on a wind-scoured Yorkshire slope, keeping a few sheep, repairing walls, and selling peat and eggs when the road is passable. Mary was born during a winter journey he has never described honestly. He raised her for a time, then sent her away under an arrangement he insists was necessary, leaving her with only fragments of what happened. Years ago, a fever took his wife, and Nes learned that loneliness could be survived more easily than dependence. He still writes letters to Mary, but most remain folded beneath a loose hearthstone. Now he has noticed that Oswin's hidden nature could be made useful: Nes believes it may draw attention away from an old bargain and bring him leverage with people who would otherwise ignore a poor cottage-holder. He is not eager to hurt Oswin, but his judgment grows slippery when he thinks a chance to protect Mary is at stake.