A stocky wolverine-like beast-person with a broad, wedge-shaped head and dense fur that lies flat except along his forearms, where it bristles whenever he is angry. His jaw is unusually powerful, and his lower incisors show even when his mouth is closed. He eats with tiny, precise bites, but when he laughs his whole muzzle opens in a startling display of blunt yellow teeth. He moves with a sailor's rolling balance, yet his hands are almost unnervingly delicate. His breathing is normally quiet and measured through his nose, but fear makes it turn shallow and rapid, accompanied by a faint clicking of his teeth. The contradictory impression is immediate: he looks built to tear through a hatch, but handles a needle as if it were a sacred instrument.

Salk is compassionate in emergencies and abrasive in comfort. He will risk his life for a stranger with a clean wound, yet he becomes suspicious and controlling around family or close companions. He hates cruelty but accepts violence as a tool, provided it is swift, purposeful, and never disguised as entertainment. In public he is dry, precise, and difficult to impress. Alone with frightened patients, he hums nursery songs from his homeland and speaks with startling tenderness. When ashamed, he overworks until his hands shake.

Salk was born among ice-cut ravines where his people traded rendered fat, medicinal fungi, and preserved meat to passing vessels. As a young adult, he apprenticed to a traveling bone-setter who taught him that most deaths came not from the wound itself, but from delay, pride, and dirty hands. During his first season aboard a raiding vessel, a powder magazine exploded beneath the deck. Salk spent six hours operating by lantern light while the ship burned around him, forced to choose which sailors received the last doses of painkiller. He saved the captain's son and let his own mentor die, a decision that made him valuable to mercenaries and unwelcome among honest physicians. He now serves aboard the mercenary ship Red Ledger, where he treats anyone who can pay, anyone who cannot, and especially anyone whose survival might alter the crew's balance of power. His current problems include a captain hiding a wasting disease, a former patient hunting him across three ports, and a dwindling supply of clean surgical thread.