The salt did nothing.
Corin knelt on the cold flagstones between his four-poster and his iron-bound trunk, his left hand pressing a pinch of coarse sea salt directly into the gray flesh of his right thumb. The skin didn't sting. It didn't weep or flush pink. It took the sharp mineral crystals the way tallow takes gravel, denting without resisting, the dead patch now stretching half an inch past the knuckle.
He ground the grains in anyway. His uncle Caractacus had kept a stoneware crock of pickling brine beneath the counter in Knockturn Alley for apprentices who handled unwashed burial rings. *Salt starves a hungry hex,* his uncle used to say, rapping Corin’s knuckles with a boxwood ruler. *It’s salt or the cleaver, boy. Choose before noon.*
Corin wiped the white crust on his knee. The gray rot didn't care about shopkeeper remedies. It was colder than the floorboards.
Across the dormitory, Gregory Goyle let out a wet, rattling snore, rolled toward the stone wall, and pulled his green velvet bolster over his ears. Theodore Nott’s bed was quiet, the heavy brocade hangings pinned shut with silver bodkins. Blaise Zabini had not turned down his sheets; his silk quilt lay smooth as stagnant water, though the boy himself was nowhere to be seen. Blaise had a way of existing only between seven in the morning and nine at night, slipping through the cracks of the castle whenever prefects started taking roll.
Draco’s bed was empty.
The velvet hangings were pulled back, tied with frayed cord. On the sheepskin rug beside his trunk, Draco’s satchel lay on its side, spilling a sheaf of ink-stained parchment into the darkness.
Corin stood up. His knees popped again, the sound loud in the damp stillness.
He waited twenty heartbeats. Down the spiral stair that led to the common room, water ticked in the pipes, a slow, regular drop against hollow lead. Further off, near the dormitory washroom, a brass tap hissed where someone had failed to seat the washer. Draco was down there, scrubbing at his arms with carbolic soap until the skin came off in red strips. He did it every night around midnight; Corin had smelled the lye through the floorboards twice already this week.
Corin stepped across the rug.
The satchel was black dragonhide, cracked along the gussets where the oil had dried out. It smelled of sulfur, bitter almond, and the scorched linen of shirts ironed too hot. Corin crouched, his good left hand gathering the leather while his right hung limp at his side, the dead thumb tucked into his curled fingers.
He was looking for the left-hand escapement wheel.
If Draco had left it loose in the flap, Corin could take it, pack his trunk, and claim ignorance before breakfast. Let Draco curse the stones; without the balance pair, the cabinet stayed dead, and Corin’s flesh might stop rotting before the necrosis hit his wrist.
He worked the brass buckle with his left hand. The tongue was bent, caught in a frayed hole. He had to use his dead right thumb as a brace. Pressing the numb flesh against the cold metal felt like pushing a block of cold suet against a blade. The skin dragged, leaving a greasy smear on the brass.
The flap came open with a dry tear.
Inside, there was no brass wheel.
There was half a loaf of stale soda bread wrapped in a handkerchief, gray with lint. Two dried swallows’ feet, their yellow claws curled tight around lead sinkers. A pair of jeweler’s tweezers, their tips blackened by fire. And stuffed into the narrow document sleeve at the back, wedged behind a half-empty tin of tooth powder, a single folded sheet of vellum.
Corin pulled it out.
It wasn't school parchment. It was thick, heavy calfskin, scraped thin enough to show the blue veins of the beast along the margin, stiff as dried horn. It had no seal, no envelope, and no address.
The writing inside had been done with a split iron nib.
The ink was dark purple—sepia mixed with vitriol—and the strokes were savage. Every capital letter leaned back like a cornered beast, while the descenders plunged through the guidelines, tearing small burrs into the vellum where the quill had gouged the skin.
Corin’s chest tightened. He knew that hand.
Three winters ago, Caractacus Burke had received seven letters from Azkaban via a licensed courier from the Ministry’s Department of Magical Corrections, each one demanding the return of a silver locket with a serpentine ‘S’ inlaid in green stones. His uncle had kept the letters locked in the copper-lined safe behind the manticore skin. *A madwoman’s script,* his uncle had told him, tapping the vitriol-eaten paper. *Look at the crossbars on the tees, Corin. She doesn't write words. She drives nails.*
Bellatrix Lestrange.
Corin unfolded the vellum. His good hand trembled slightly, making the stiff sheet click against his fingernails.
There was no greeting.
*The iron must take the draft before the solstice,* the letter began, the ink so thick in places it formed shiny black scabs on the page. *Your father sits in a cellar eating boiled oats out of tin, Draco. Every hour you waste whimpering over splinters is an hour he spends on his knees. The dark gentleman does not ask for excuses; he asks for the latch to drop. If you cannot align the wood, use bone. It conducts the hinge just as well. I have told you what to sing to it. Sing it until your throat bleeds. If the girl’s necklace failed, it is because you were weak with the dosage. Do not be weak with the door.*
Below it, written in the same violent, jagged hand, was a string of six runes.
Corin stared at them.
They were not standard elder Futhark. They were Elder-branch variants, used exclusively in sixteenth-century necromantic bindings to tether a wandering soul to an unmoving vessel. The third rune had a slash across its diagonal leg—a cancellation mark. It meant whatever passage was being carved through space was designed to accept traffic only one way.
A slaughter gate.
A sound scraped on the stair.
Corin froze, the calfskin stiff between his fingers.
A soft, dragging step on the spiral steps. Then the wet, heavy smack of bare feet on cold limestone.
Corin didn't have time to refold the letter along its original creases. He shoved it back into the satchel’s rear sleeve, his numb thumb catching on the buckle, tearing a flap of gray skin loose near the nail. He felt no pain, only the dry crunch of dead tissue against the leather. He let the satchel drop, stepped backward in three silent strides, and slid between the green velvet curtains of his own bed just as the latch on the heavy oak door turned.
The door swung inward with a low groan.
Draco stood in the opening.
He wore only his trousers and an undershirt, soaked through with gray water around the collar. His hair hung in greasy, yellowed points over his forehead, dripping onto his nose. His forearms were raw, scrubbed so violently with carbolic that the skin looked like scalded pork, but beneath the red irritation, his knuckles were gray-white with exhaustion.
Draco didn't look at Corin’s bed. He didn't look at Goyle, who gave another wet, choking snore.
He walked to his trunk, his bare feet leaving damp, smudged prints on the stone. He dropped to his knees.
For a long minute, he didn't move. He sat there, his shoulders hunched, his wet ribs heaving in jerky, shallow spasms that shook his whole frame. Then, slowly, with hands that shook so badly he could barely manage the leather, he reached into his satchel.
Corin watched through the gap between his curtains.
Draco’s fingers went straight to the back sleeve.
He pulled the vellum out. He didn't read it. He pressed the stiff sheet to his face, his eyes squeezed shut, inhaling the smell of the ink and the vitriol until his chest hitched with a sound that was half-sob, half-gag.
"I'm trying," Draco whispered to the empty room. His voice was thin as water, cracked down the middle. "I'm doing it. I'm doing it, Auntie."
He shoved the letter back inside, scrambled into his bed, and pulled the hangings shut. The brass rings shrieked along the rod.
Inside his own dark bed, Corin sat with his back against the bolster, staring down at his right hand.
The thumb was ruined.
Where the buckle had caught the skin, a thin, colorless fluid was oozing out, pooling in the crease of the first knuckle. It smelled faintly of vinegar and pond water. But worse than the smell was the new thing—a thin, black thread, no thicker than horsehair, that had appeared under the skin on the back of his hand, creeping out of the gray deadness and pointing straight toward his wrist.
It was tracking a vein.
*If you cannot align the wood, use bone.*
Corin looked at his penknife on the bedside table.
He picked it up with his left hand. The horn handle was cold. He flipped open the curved pruning blade—the one his grandfather had used for cutting back mandrakes before they grew teeth. He held the blade over the black thread.
If he cut it now, he would bleed through the mattress. The smell would wake Nott. Snape would know by dawn; the Potions master kept charms on the dormitory drains to detect dark substances washed out of wounds.
Corin let the blade drop to his thigh.
He knew what the poison on the brass cog was now. It wasn't shop rot. It wasn't the grease of an old French scrying clock.
It was the sap from the cabinet itself.
The wood of the Vanishing Cabinet was dying from whatever Bellatrix had told Draco to sing into it. The necromantic runes were poisoning the frame, turning the black walnut into something that fed on whatever was fed through it. Draco had tried to force the left-hand escapement into the hinge while the cabinet was still drinking, and the metal had caught the blight.
Draco wasn't repairing a passage. He was nursing an infection.
Corin leaned his head back against the cold stone of the dormitory wall.
Outside, the wind coming off the Black Lake hit the high towers of the castle, a long, hollow shriek that vibrated down through the foundation. Deep under the floor, something shifted in the sediment—a massive, sluggish movement of cold water that made the green lantern swing six inches on its iron chain.
Ten o'clock tomorrow night. Behind Boris the Bewildered.
Corin had promised to bring the matched pair of brass wheels. He had promised to grind the sleeves down so they would slide clean into the spring housing.
He reached down with his left hand and took hold of his dead thumb. He twisted it, hard, until the bone grated inside the numb joint.
Nothing. Not a flicker of heat. Just the dull sensation of meat shifting against meat.
He let go.
In the dark behind the curtains, Corin didn't think about his two Galleons. He didn't think about the scrying clock or the winter frost on the Quidditch pitch. He thought about his uncle Caractacus standing behind the counter in sixty-four, holding the severed front half of a wizard who had arrived late from Yorkshire, looking for the silver watch in the waistcoat pocket before the Aurors arrived to haul the mess away.
His uncle had kept the watch.
*Never leave clean brass on a dead man, Corin,* the old man had said, scrubbing the blood out of the balance wheel with a wire brush. *He doesn't have any more use for the hours.*
Corin closed his eyes.
The castle groaned above him, stone grinding against stone, and beneath his ribs, his heart kept beating out its hard, uneven rhythm, perfectly matched to the drop of the water in the pipes.
***