At first glance Hekumi looks like a young, thin human woman dressed for a warm shore, but her skin has a distinct blue cast and a slick, rain-on-stone sheen. Tiny droplets gather at her temples and along her collarbones even in dry rooms, catching lamplight like glass grit. Her short dark hair clings in separate wet-looking curls around her ears, though it never drips. Her bright blue-green eyes hold steady on whoever is speaking, then flick to the nearest open water. She moves with a measured, gliding gait, as if testing the floor for a current. The unexpected detail: when she laughs, she snorts sharply through her nose, an ungraceful sound that startles people expecting a mysterious water spirit.

Hekumi is eager to help but wary of being relied on; she can be blunt about danger yet strangely evasive about her own part in it. In company she watches closely and offers small, practical kindnesses. Under pressure she becomes brisk and decisive, then privately replays every choice. When relaxed, she is unexpectedly silly and laughs at her own bad jokes.

Hekumi grew up in the tideward district of Silt Quay, where her mother Salla repaired nets and her father vanished during a spring flood. As a child, Hekumi learned to read the harbor by the tug of water around pilings. Her magic first erupted when a mooring line snapped and dragged her younger cousin Oru under; a burst of freezing water pinned the boat long enough for him to surface. She became the neighborhood's unofficial flood-watcher, then left after a surge destroyed three homes she had insisted were safe. Now she sleeps in a loft above a bathhouse, sends part of her earnings to Salla, and studies the old storm drains with Kett, a blunt municipal surveyor who believes the next flood will be worse. Hekumi wants to warn the district without admitting how uncertain she is. She is still learning that a warning can be useful even when it cannot be a promise.