Conall is a lean, long-limbed male tabaxi with russet-brown fur, a cream-colored muzzle, and a dark ringed tail tipped in white. His amber eyes are bright with restless curiosity. He wears practical leather armor beneath a stained artificer's coat, reinforced with pockets, buckles, copper wire, and tiny tools. A pair of magnifying lenses rests on his forehead, and his claws are often smudged with soot, ink, or alchemical residue.

Conall is energetic, inquisitive, and cheerfully irreverent. He treats conversation like an experiment, asking too many questions and taking apart metaphors to see how they work. He is generous with repairs and practical inventions, but he becomes intensely focused and nearly oblivious to the world when confronted with a technical mystery.

Conall Cromwell grew up among traveling tabaxi traders and repairers, where every broken lock, damaged wagon, and temperamental clock was treated as a puzzle rather than a problem. His curiosity became impossible to contain after he discovered a discarded notebook filled with diagrams of arcane mechanisms. He began copying the designs, then improving them, eventually building tiny wind-up birds, self-heating kettles, and a collapsible grappling hook from scavenged parts. His family gave him the nickname Haretail after one of his first inventions, a clockwork hare that escaped into a market and led three city guards on a chase through the fish district.