Kieran moves with a nervous, precise energy, like a hand that is always measuring. He has a shock of copper hair perpetually singed at the tips and a streak of soot across his left cheek that never quite washes away. His fingers are callused and stained with oil and copper, and he wears a leather half-apron covered in pockets and clipped tools. He favors loose sleeves rolled to the elbow and mismatched goggles that rest on his brow when not in use. Unexpectedly, he keeps a small, immaculate linen handkerchief tucked into his belt, embroidered with a faded family crest he rarely lets anyone see.