Molten Frost

In the city of Anthracite, the ground burns, the sky rains ash, and touch is a lethal necessity. Built atop an eternal subterranean fire, the city is a crumbling industrial nightmare. The poor swelter in "The Smolder, " a district of unbearable heat, while the elite hoard imported glaciers in "The Fridge." Survival is a constant war against the elements. Elara is a "Sun-Kin." Born with a curse that keeps her body temperature at a lethal fever pitch, she is a living furnace.
She cannot feel cold, only an internal, consuming fire. The local Guild uses her as a human kiln to smelt rare ores, but her own heat is slowly killing her, burning her alive from the inside out. Kaelo is a "Voidwalker." To survive the deep mines, he underwent an alchemical procedure that replaced his blood with sub-zero coolant. His skin is frost-bitten blue, his touch causes instant necrosis, and he feels no heat, only an agonizing, eternal freeze.
He is the Guild's hunter, a monster of ice sent to execute Sun-Kin who are about to explode. When Kaelo is ordered to extinguish Elara, everything changes. Instead of death, their contact brings the one thing neither has ever known: relief. His lethal cold soothes her burning veins; her infernal heat warms his frozen core. They are biological opposites, yet the only two people on earth who can touch each other without pain.
Now, bound by a thermodynamic need that defies the Guild's laws, they must uncover the truth beneath the city's fire. But the balance is fragile. If they stay apart, they die. If they get too close, they risk triggering a reaction that could crack the world apart. She burns. He freezes. Together, they are the storm.