A lean, weathered human woman with deep brown skin, tightly curled black hair cut close at the sides, and sharp hazel eyes flecked with green. Salt has roughened her hands and lightened the ends of her hair. She wears practical leather armor beneath a faded blue-gray sailor's coat, carries a wooden shield marked with tide lines, and keeps a carved piece of driftwood tied around her wrist.

Ketu is blunt, alert, and irreverently practical. She trusts people who can admit fear without becoming useless, and she has little patience for anyone who mistakes authority for competence. Beneath her hard-edged humor, she is observant and protective, especially toward animals, deckhands, and anyone who has been abandoned by a crew.

Ketu Adeyemi was born in a busy coastal port to a family of dockworkers, fishers, and small-boat pilots. As a child, she learned to read weather from the color of the horizon and to judge a current by the way floating scraps turned in the water. She joined a merchant vessel as soon as she was strong enough to haul rope, eventually becoming a competent deckhand and navigator. During a voyage through a season of unnaturally calm seas, the ship drifted for three days without wind. Ketu heard something singing beneath the hull and followed the sound in a dream, where a vast green presence taught her the first secret of the druidic tongue.