In daylight, Dr. Lyman Harris was the most forgettable of men. A pathologist by training, he worked in the sterile basements of St. Erasmus Hospital, cataloging causes of death with the same detachment he once used for collecting moths as a boy. But at night, Lyman left his locked apartment, barefoot, eyes glazed like blown glass, and roamed.

No one knew at first. It was only after Mrs. Dobelin, the ancient widow in 4C, began finding muddy footprints outside her backdoor and her cats disappearing one by one that the rumors started. “Sleepwalking,” someone said. “Somnambulism,” corrected another, trying to sound educated. Theories bloomed like fungus. Drugs. Satanism. A cult.

They didn’t know Lyman was no longer human in the dark.

His dreams were black and weightless. There was no vision, no voice, just the call of some hunger. It began three months ago, after the accident, when Lyman performed a hasty autopsy on a vulture brought in by local wildlife control. The bird had been feeding on livestock infected with anthrax. The attending techs had gagged and left the room, but Lyman had stayed. It intrigued him. How could this creature feast on rot and walk away unscathed?

He found answers in the bird’s blood. Acid strong enough to dissolve bone. Antibodies to botulinum and anthrax like ancient shields. The gut, a festering cathedral of death made sacred by resistance. It was not immunity. It was dominion. And something inside him wanted that.

The first night, he dreamt of biting into the flank of a roadkill deer. He awoke barefoot in bed, his feet muddy and lips streaked with black. He assumed it was a dream. Until it happened again. And again. He began waking with bits of fur under his nails. One morning he found a raccoon paw in his mouth. Then the dreams changed: he was flying, not walking. His arms wide, catching thermals over the highway. He circled bloated deer, watched from above, and descended like judgment. What should have killed him never did. He consumed meat green with decay. A bloated fox leaking bile. Maggots writhing like caviar. Once, a dog carcass laced with antifreeze. He vomited only once, and even that tasted sweet on his tongue.

He felt no sickness. No fear. Instead, a kind of clarity. A peace.

Lyman began recording himself. He installed cameras, trying to catch the nocturnal wanderer. But every morning the files were gone, erased, or corrupted with strange, screeching audio that sounded like wings and wind over stone. In time, he stopped locking the doors. Why pretend? The beast inside him was him now.

One morning, after a particularly vivid blackout, he woke in a park. His clothes stiff with dried blood. A man was dead nearby, throat torn open, ribs cracked, face eaten away like bark stripped by fire. His wallet said Father Jules Montgomery. The police would find the body in hours. Lyman calmly walked home.

He came to believe he was chosen. Not cursed. Not sick. But evolved. He recalled something from childhood: a Persian myth about ḠUL, demons of the desert who walked like men by day but fed on corpses by night. Not evil, simply necessary. Cleaners of the dead. Priests of rot. And hadn’t vultures once been considered sacred? Lyman began experimenting. Injecting himself with strains of botulinum toxin. Anthrax. Cholera. Nothing happened. No fever. No paralysis. Not even a twitch. He was becoming something new. Something posthuman. A noctambotulist, one who walks in sleep, but feasts on death.

By the time the city connected the dots, the missing pets, the desecrated graves in Resurrection Park, the half-eaten coroner’s assistant, it was too late. They raided his apartment. Found walls scrawled with anatomical sketches of vultures and mythological creatures: ḠUL, wendigos, preta with distended stomachs and weeping eyes. In the freezer: raccoon skulls, cat vertebrae, human femurs boiled clean. But no Lyman. Only feathers. Only claw marks on the fire escape.

Some say he still walks. That on moonless nights, in suburbs and slaughterhouses, you might glimpse him hovering over a fresh body, his mouth smeared with rot, eyes dull with sleep, but smiling. A noctambotulist. A man who found peace in Decay.