The guards heaved Sabina and Gavril through a narrow, dripping archway, the air instantly thickening with the scent of ancient stone and ice. The passageway twisted, a calcified artery burrowing deeper into the colossal ribcage, until it opened into a cavernous chamber. Jagged, fossilized bone fragments clawed at the air above them, forming a vaulted ceiling that disappeared into absolute darkness. The floor was a treacherous mosaic of frost-slicked rock and stagnant pools of black water, reflecting the occasional, sickly green glow of phosphorescent moss. The cold smelled of calcified marrow, coating their tongues with bitter salt. “Insolent whelps,” one guard grunted, shoving Gavril forward. He stumbled, catching himself before he could fall into a puddle. Sabina, still held tightly, scanned the space. It was immense, a segment of forgotten history. Near the far wall, a sulfurous vapor hissed up from a split flagstone. A volcanic flue. Efficient. Stage one of site stabilization. The guards pushed them both roughly into the chamber, the heavy iron door clanging shut behind them with a finality that vibrated through the Leviathan’s very bones. She took inventory with the detached speed of an auditor on a loading dock. Gavril, pale and shivering, hugged himself, his breath pluming in the frigid air. “Significant gradient,” Sabina muttered aloud. She pulled her arm free, striding with purpose toward the steaming haze. “We have roughly forty minutes before fine motor control fails. Relocating to the heat source.” Gavril watched her, bewildered, as she navigated the treacherous terrain, her dark dress surprisingly agile over the slick rocks. He followed, drawn by her sheer, unyielding pragmatism. The crack discharged a steady draft smelling of rotten eggs and boiled stone. Sabina hovered a bare palm over the gap. “Sufficient draft for survival,” she said. She removed her heavy shawl, spreading it over a relatively dry, flat patch of rock near the vent. “Sit,” she ordered Gavril. “Closer to the seam, unless you want to lose toes.” Gavril hesitated, lashes frosted with sleet, then crumpled onto the shawl. The rising sulfur air cut through his frosted doublet. He shivered, a theatrical tremor that started small and escalated into a full-body seizure. His teeth chattered, his lips turning a faint blue. “Sabina,” he gasped, his voice thin, “I… I can’t feel my extremities. The cold… it’s a living thing. It’s crawling into my marrow.” Sabina, busy inspecting the rock walls for any loose debris that could serve as insulation, paused. She knelt beside him, pressing a cool hand to his forehead. “No fever,” she observed. “Skin is clammy, pulse sluggish. Risk of hypothermia. Contingency required.” She hauled him against her chest, pinning him between her ribs and the slate to seal out drafts. Gavril froze, then buried his nose against her collar, inhaling her smell of dried cloves and hot pig fat. His shivers subsided, replaced by a contented sigh. He closed his eyes, a small, triumphant smile playing on his lips. Just then, a faint clinking sound echoed from the heavy iron door. Gavril’s eyes snapped open, a flash of irritation in their depths. Mirela’s face, pale and etched with concern, appeared between the bars of the small, grated window set high in the door. “My lady!” she whispered, her voice strained. “Are you unharmed? I bribed the guard… I brought supplies.” She shoved a heavy woolen quilt through the iron grate. Gavril’s arm, which had been loosely draped around Sabina’s waist, tightened possessively. He lifted his head from her neck, turning a venomous, unwavering glare on Mirela. His dark eyes, usually shadowed by a feigned innocence, now burned with an intensity that promised retribution. The message was clear: *Mine.* Sabina tugged the quilt free with one brisk yank. “Solid logistical support, Mirela,” she called over the prince's shoulder. “Asset preservation improved sixty percent. Dismissed.” Mirela caught the young prince's bared teeth and vanished into the corridor. With the quilt pinned across them, Sabina inspected her coat pockets as her stomach gave an audible groan. “Blood sugar crashing,” she muttered. “Work output requires fuel.” She produced a small, oil-stained pouch from her pocket – a habit from managing kitchen emergencies – and rummaged inside. “Smoked pork link, dried parsnip shavings, and a heel of rind-cured cheese. Standard salvage.” She began to chop the sparse ingredients with a small, sturdy knife she always carried, placing the pieces onto a flat, clean stone she’d found. The thermal vent provided an excellent, if unconventional, cooking surface. The scent of rendered lard and toasted parsnip cut the bitter stench of lime. Gavril watched her blade scrape sizzling fat across the slate. Her hands moved with the ruthless economy of a meatpacker on the clock, unhurried, steady, indifferent to the dungeon gloom. He had known only poisonous courtiers and groveling lackeys. Sabina fed him like a stray hound, shoved coal into his belly, and treated his despair like a scheduling conflict. He coveted every calorie she pushed down his throat. Her steady hands, her dry voice, her relentless domestic aggression. A cold, possessive certainty settled deep in his gut, eclipsing the hunger for the ash-beasts, overshadowing the bitterness of his past. He would not, could not, let her go. Not ever. Just as the hash began to turn a promising golden-brown, a guttural shriek tore through the silence of the oubliette, rattling the very bones of the Leviathan. The iron door, thick and supposedly impregnable, groaned, then splintered with an explosive roar. A towering beast built of churning cinders and soot hurtled into the cell. It was larger than any horse, with glowing crimson eyes and claws like obsidian shards, radiating an aura of profound, agonizing hunger. Its raw power thrummed, vibrating the air, a primal force unleashed. Gavril froze against her shoulder, his jaw locking as his pupils dilated into twin abysses. The manifestation crept forward, sniffing the grease-scented air, fixating on Sabina. Sabina, however, barely registered the terrifying apparition. Her immediate concern was the integrity of her cooking surface. “Unacceptable,” she muttered, checking the iron plate. “Breach of perimeter. My sear is ruined.” She scowled up at the nightmare, which opened jaws made of interlocking cinder needles. “Energy expenditure for a creature of that mass must be astronomical,” she mused aloud. “It probably needs a significant caloric infusion.” Without blinking, she grabbed a charred chunk of pork from the rock. “Down,” she barked, flicking the morsel like scrap meat to an unruly terrier. “Eat and settle.” The apparition snapped its maw shut, the burning embers in its gullet guttering out. It locked its glowing sockets on the spinning bit of salt-pork. The fat hit the flagstone with a dry slap. The nightmare stooped, vacuuming the fat through soot-rimmed nostrils, and let loose a grinding, contented purr that shook the dust from the ribs above.

Thermal Vents and Ash-Kittens