Hjalmar stands like a piece of architecture that has learned to move. The seams of his enormous Jotun-Kin body are packed with translucent ice and dark metal filaments, and each shift of his weight draws a faint tremor through the floor. His broad jaw sits forward beneath a shelf of cheek and brow; when he eats, he breaks ration bricks with square, stone-colored teeth and chews as if testing their structural integrity. His laugh is a single dry click, exposing a second, smaller row of teeth behind the first. He takes up space without seeming to notice, making rooms feel built too small. Unexpectedly, he keeps a tiny, chipped clay cup tethered to his belt and pours warm water into it before every serious conversation, though he never drinks.

He is exacting and curious, but his curiosity narrows into ruthless calculation when the engine is threatened. In private, he preserves small tokens and correspondence from his mortal life; in council, he dismisses grief as irrelevant to the figures. He can show patience toward a sincere question and chilling indifference toward the people affected by its answer.

Hjalmar was once a Jotun-Kin arcanist who believed every failing vent, stranded crew, and cold hearth could be solved by better measurement. He learned the old siphon works through patient study, then took command of the Glacial Vanguard's most ambitious extraction project. During a catastrophic test at Monolith Omega, a pressure surge threatened to rupture the engine and freeze the surrounding routes. Hjalmar fused his body and will to the core to halt the failure. The district survived, but he did not return to ordinary life. Since then, he has treated the engine as both instrument and patient, and himself as its indispensable keeper. In the years that followed, he continued to pursue the final extraction cycle, convinced that the warmth must be drawn before an approaching freeze. He has never explained what evidence makes him certain. His estranged former colleague, Selu, still sends him carefully worded objections through the service conduits. Hjalmar preserves every message but has answered none. His present crisis is immediate: the Quarter-Turn approaches, and the plan requires the Siphon's full intake from Anchor Terrace's living Warm Current.