I Reincarnated as a Demon King,I Will Kill Everything

We left Crowmere before the sun finished crawling over the hills.

The last fires were still breathing smoke through the ribs of the cathedral when Rena opened the gate. Her blades crossed in front of the shattered altar, black light braided between them, then tore a wound in the air. The smell of ash became the smell of iron and old thunder. Cold wind rushed from the cut as if the world were exhaling.

"Home," Selena said, voice low. Her halberd tapped stone, leaving a trail of frost that hissed when it touched the gate's edge.

"Move," I said.

My demons obeyed. Nana marched the vanguard—shield up, chin down—her steps steady despite the dried blood on her armor. Malrik limped with a bone-rod as a crutch, one eye wrapped in shadow bandage. Clarissa carried two wounded on a sling of hardened blood, face set and unreadable. Zereth walked last, hood thrown up, aura stitched together by a soul that wasn't his. He did not look at me. He didn't need to. The chain between us was quiet and strong.

I entered the tear and fell into the old dark.

Hell received us like a furnace that had learned patience. The sky was a roof of stone veined with red light, pulsing like a slow heart. Black mesas rose from an ocean of ash; rivers of molten iron crawled through canyons, sparking where they kissed the basalt. The air tasted like a coin held too long in the mouth.

Noa's voice hummed in the gauntlet. "Anchor acquired. Coordinates: Black Hollow, Outer Court of the Abyss. Conclave paths within one hour, My Lord."

"Good." I lifted my hand. The Silent Crown unfurled like a black flower over our heads, pressing down the heat and dust until the air grew cool and heavy. "Camp. Then drills."

Selena's smile sharpened. "At last."

Even tired, even bleeding, my demons were hungry for the weight. We had learned the truth on the surface: if you can train under a mountain, you can fight under the sky. I led them to the practice grounds we carved months ago—an arena of cracked obsidian ringed by rune pylons. The pylons remembered us; their faces opened in thin lines, and the gravity runes woke with a hoarse whisper.

I set the first ring to one hundred and twenty times mortal pull.

The world slammed down.

Knees hit stone. Armor screamed. The ash around us puffed into perfect circles as bodies met the ground. Only four demons kept their feet: Rena, Selena, Nana… and Zereth, trembling, refusing to kneel.

"Rise," I said.

They did. Slowly. Muscles quivered. Teeth ground.

"Listen," I continued, voice level. "The Church will not bring us fair fights. They will bring relics, vows, and borrowed light. We do not answer with light. We answer with weight. Your bones must love it. Your lungs must drink it. Your hearts must beat inside of it."

Noa clicked softly. "Recommendation: cadence training. Anchor breaths. Four-count descent, two-count hold, four-count ascent. Repeat until collapse."

"Do it," I said. "Rena—count."

Rena's voice cut the air like a metronome. "Down—two—three—four. Hold—two. Up—two—three—four."

They moved together. Squats under a sky that wanted to grind them into powder. Push-ups until elbows shook. Carries with basalt blocks shaped like tombstones. When a demon fell, I tapped a rune and added five more weights to everyone else. Pain climbed like a tide.

Zereth lasted longer than he should have. His soul still had seams, and pain leaked through them; I saw it in the way his hands shook between breaths. But he did not stop. When his knee finally kissed stone, he rose before it could settle.

"Again," he rasped.

"Once more," I agreed. "Not again."

Training is a knife. The right edge teaches. The wrong edge ruins. I would not ruin what I had just bound.

Two hours passed. Sweat ran into ash and made black mud. Breaths turned into smoke. No one asked for mercy, because I had already told them mercy was a lie.

When I lifted my hand, the pylons sighed and the world's weight loosened.

Nana fell to one knee, shield as a crutch, lips white and cracked. "My Lord—permission to vomit and then resume."

"Granted," I said.

She turned aside and emptied herself quietly, then wiped her mouth and went to stand again. Selena laughed, delighted, then coughed blood into her gauntlet and smiled wider.

"Water," Clarissa said to the line. She cracked a thin crimson flask and misted their mouths with cooling blood. The steam lifted from their tongues like ghosts.

Noa counted in my head. "Survival probability increased by seventeen percent against crusader formations. Additional gains require domain weaving. Suggest next block: Crown threading."

"Set the spires," I ordered.

Rena and Selena moved together, planting four needle-spires at the arena's corners. Shadows stretched between them like silk threads.

"Thread one," Noa said. "Balance the edge."

The Silent Crown unfurled again, thinner this time, a veil instead of a wall. I taught them how to place it along the ankle, the wrist, the throat—structure over spectacle. A good domain was not a storm; it was a net.

"Thread two," Noa continued. "Pinning."

We drove shadow-pins into our own joints and learned to move around them—how to pivot when the knee refused, how to punch when the elbow was trapped. The first to master it would make enemies feel the same trap without noticing the moment it closed.

"Thread three," I said. "Mute."

It was my favorite. The world went quiet until the sound of a heartbeat was a drum, until a blink was a hammer. Inside that pressure, fear revealed whether it was a weakness to crush or a leash to grab. Nana shook the first time and looked at me the way soldiers look at a cliff over a black sea. The second time, she smiled into it.

When they swayed, I let them sway. When they fell, I let them taste stone. Then I raised my hand and gave them back air.

"Enough," I said at last. "Eat. Clarissa—feed the slowest first."

"Understood," she replied. Her tithing was efficient: a nick of wrist, a drop of cold blood on the tongue, a map of who needed what and why. She did not ask who was worthy. She calculated who would die first and erased the numbers.

I turned away. Noa dimmed the Crown around us and warmed the gauntlet's inner plates, like a hearth for a single hand.

"Report," I said.

"Crowmere fallout complete," Noa replied. "Surface response: high. Church mustering crusade. Time to first strike: three to seven days. Probability of relic deployment: seventy-nine percent. Probability of hero core involvement: unclear. Kravius resonance detected south by southeast—distance indeterminate."

I listened to the stone. Hell had a way of telling truths if you put your ear to the right vein. There was nothing to hear yet. Silence can be an answer too.

"Conclave?" I asked.

Noa flickered. "The summons arrived while you trained. The other thrones know Crowmere's bell went silent. They're watching. Some want to test. Some want to feed. The Black Spire opens at the next magma rise."

"Then we go," I said.

Rena stepped to my shoulder. "My Lord, if the other kings wish to bleed us before we build—"

"They won't," I said.

She looked at me, calm. "Because you will not let them, or because they will choke on the attempt?"

"Yes," I said.

She smiled without showing teeth.

We marched at the red dawn—if "dawn" is the right word for when the ceiling veins pulse brighter and the heat tries harder to be your skin. The Black Spire rose like a broken fang from the center of the Hollow, its flanks carved by hands that remembered what knives had taught them. The front doors were basalt slabs banded with iron bones. They opened because they knew my aura. Or because they liked the taste of it.

Inside, the Conclave waited. A ring of thrones encircled a pit where magma braided itself into ropes and unbraided again. Each throne was a story with a spine and teeth.

On the northern throne, a woman sat like an avalanche deciding when to fall. Her hair was cinders in a wind that didn't exist; her crown was a loop of slag that never cooled. The Queen of Cinders—Morgra. Rumor said she ate volcanoes. Rumor often undershot.

To the east, a thin, long-limbed creature lay sideways across a chair of ribs, smiling with too many teeth. Shadows pooled in his lap like obedient cats. The Whisper King—Noxil. If you gave him a secret, you bought your own leash.

On the west, a banker's nightmare in iron plates—Baelor the Tally Tyrant—sat surrounded by chains that counted, weighed, taxed. You could hear sums happening around him. Numbers do scream if you listen.

On the south, nothing sat, and that was worse. Emptiness in the shape of a throne. The Seraph of Rot—Ilyx—never arrived like other people. He arrived to places other people had already rotted.

Two lesser thrones were empty. Two more were filled by pretenders who wanted to be important to the story.

I walked to the center of the ring. Selena and Rena flanked me. Zereth stood a step behind, hood low, an anchor humming under his ribs. The rest of my demons waited a safe distance from where kings solved math.

"Neil," Morgra said, the name a soft crackle. "Crowmere sang your name, then choked on it. The surface stinks of you."

"Good morning," I said.

Baelor's chains rattled like a laughing abacus. "The tithe of panic has begun topside. Every prayer is a coin. Every coin rolls to me. Keep frightening them, and we will be rich."

Noxil's grin widened. "We are already rich in stories. A hero king who changed sides twice and changed bodies once. Your pet blade whispers, by the way." His eyes glinted at my gauntlet. "Tell it to hush. Its arithmetic bothers me."

"No," Noa said in my ear, dry. "He bothers me."

I did not smile.

Ilyx arrived the way rot arrives: first as smell, then as stain, then as fact. The empty throne turned green through the iron; moss crawled from nowhere, sighed, and died. A figure leaned where there had been absence, feathers ruined, wings inverted, eyes like old wounds.

"Crowmere spoiled," Ilyx croaked, voice a handful of grave dirt. "Thank you, child."

I was older than all their prayers and younger than all their grudges, depending on which life you counted. It didn't matter.

"I didn't come for praise," I said. "I came for lines."

"Lines?" Baelor asked.

"Borders. Claims. Hunts. If the surface is a table, we decide who eats which corner. If we brawl here for scraps, the Church gets fat."

Morgra's fingers drummed the arm of her throne. Each tap dropped cinders into the magma and made it purr. "You speak like a king."

"I am one."

"Some of us were kings before you learned the shape of a throne," Noxil murmured, amused.

"And some of you stayed kings so long you forgot how to stand," I said.

Silence cut thin and clean across the pit. I did not raise the Crown; I let the word do it. Words can weigh as much as stone if you set them right.

Morgra smiled then, a slow heat. "Good. We needed a rude one."

Baelor counted the air. "Proposal?"

"Three things," I said, holding up the gauntlet. The rainbow-black gems shivered. "First: non-interference pacts for our opening moves. One realm, one strike, one month. If you raid my line while I salt the Church, I won't argue. I'll erase your ledger."

Baelor's chains whispered, calculating loss. He nodded once. "Conditional acceptance. The tally likes order."

"Second," I continued, "relay law. When the Church marches with relics or heroes, the closest throne answers the bell—no excuses. We can murder each other later. For now we bleed the same enemy."

Noxil chuckled. "Togetherness in Hell. Charming. Still—accepted."

Morgra watched me with hot eyes. "Third?"

"Fragments," I said. The word tasted like old bronze. "We stop skulking for Amon's bones in the same holes. We share maps. Whoever finds a fragment calls a Conclave. Anyone who tries to hide a piece will be eaten by everyone else."

Baelor hissed, chains tightening. Greed is a spine that bends in one direction only. Ilyx smiled—nothing nice in it.

Noxil tapped his teeth, thinking. "And who holds a fragment if they find it?"

"The one who rips it out," I said. "But the rest watch. We all learn what it does on a body. No more fairy tales."

Morgra laughed, delighted. "At last. Honesty as a weapon."

Ilyx's feathers shivered like a grave shaken by a heavy footstep. "Accepted," he rasped. "If only to watch who breaks first."

Baelor's chains unwound half a turn. "Conditional accepted."

Noxil's shadow crawled up the back of his throne, listening to his own grin. "Accepted with interest."

The runes around the pit burned brighter as if the Spire approved. The magma climbed its ropes and clapped.

"Good," I said. "Then my line runs through the western holy road. Cathedrals, pilgrim towns, granaries, and the vaults under them. I will crack them open. If you smell spice and tallow, it's mine."

Morgra leaned forward, chin on fist. "Leave me the forges of the south. I will trade you steel for grain."

"Done."

Baelor rattled. "I will harvest cities that tithe to the east. Their ledgers insult me. They will be corrected."

"Fine," I said. "Just don't tithe my dead."

He grinned with coin-bright teeth. "Perish the thought."

Noxil waved a lazy hand. "Give me the monasteries. I am hungry for secrets."

"Eat them," I said. "But if one of your secrets spells my name, whisper back."

His grin didn't move, but his eyes did. "Naturally."

Ilyx didn't speak. The rot around his throne spread a hand-span farther, then stopped, respectful, like a dog that knows the line you drew in the dirt.

The Conclave ended the way good meetings should: without applause. We stood. We inclined heads. We did not turn our backs too far.

On the way out, Morgra fell into step beside me, radiating heat that turned stray ash to glitter.

"You carry a mask," she said without looking at it. "And the mask carries a woman who hates and loves you both."

"Not anymore," I said. The topeng of Celes warmed on my belt, faint holy ember caged by demon iron. "She burned. She stays useful."

Morgra's teeth flashed. "You're going to be fun."

"I'm going to be king," I said.

"You already are. That's why you're fun."

She left me with that.

Noxil spoke from a shadow I did not remember making. "Kravius breathes," he said. "He has many throats. I know which one bites next."

"Where?"

He tasted the word like wine. "If I sell you that, you owe me a story."

"You already have one," I said. "Crowmere."

"Hmm," he said, pretending to be bored. "True. Very well. A vessel waits in the mountain city of Lumen. A sword vault. A priest who is also a scabbard. Cut him, and the blade inside screams."

"Thank you," I said.

He bowed deeper than necessary. "Buy better lies next time. These were too easy."

I kept walking.

Baelor didn't bother with us. He was counting a pile of invisible debt like a man petting a beloved dog.

Ilyx watched me leave with eyes that had seen the first grave and planned the last. Rot has patience. It believes every victory is a delay.

Outside, the heat softened. My demons were waiting where I left them, not slouching, not talking. Rena stepped forward at once.

"Well?" she asked.

"We have a map," I said. "And a month where friends won't stab us in the spine. After that, we go back to normal."

Selena laughed. "Normal," she said, tasting the word like blood. "I missed normal."

"Eat," I told them. "Then more work."

"Gravities again?" Nana asked, voice dry.

"Worse," I said. "Weaving."

Noa clicked. "I have a sequence."

"We'll use it," I answered. "After that we hunt a priest who is also a scabbard."

Clarissa raised an eyebrow. "That is a terrible metaphor, My Lord."

"It's not a metaphor," I said. "It's an address."

They didn't laugh. Good. Humor loosens hands. I needed them tight.

The drills that followed were different from the first. Not heavier—smarter. We ran anchor-cadence with breath candles that went out if you lied to them. We tied wrist to ankle with shadow string and learned to fight like broken puppets. We practiced killing without sound until even the clack of teeth was a crime. When someone failed the mute thread, we started over from zero. No one failed twice.

Zereth held. The soul I had pressed into him settled deeper each hour, like dye finding the cloth it deserved. He moved better when he forgot whose color it was.

Rena's domain grew colder, tighter, more exact. She could place a silence the size of a coin on your tongue and make you swallow it. Selena's frost learned manners; it asked bones to break and they agreed. Nana's shield ‒ that simple, honest tool ‒ learned how to lie, how to show a gap that wasn't there and hide the one that was.

Malrik called smaller beasts from smaller cracks. Quality, not size. The best wolves are the ones you don't hear.

Noa whispered through all of it, counting, measuring, suggesting, never nagging. A good blade doesn't tell you you're weak; it shows you how to cut.

When night returned—if that's what you call when the ceiling veins dim and the stone breathes out—we ended. I stood at the arena's edge and looked at my demons. They looked back, heavier than morning, and smiled like knives that had found a whetstone.

"Tomorrow we move," I said. "The mountain city. The scabbard priest. Then the Highest Cathedral."

Rena bowed. "Yes, My Lord."

Selena spun her halberd and let it land with a crack that echoed like a promise. "Will there be screaming?"

"Only theirs," I said.

Nana lifted her shield a fraction higher. Clarissa rolled the stiffness from her shoulders. Zereth said nothing, but his hood rose a little with his breath, and the anchor under his ribs thrummed once like a deep drum.

Noa's voice was a quiet coal. "Crown integrity: eighty-one percent. Troop rhythm: coherent. Probability of success against an unprepared relic vault: high. Against a prepared one: still acceptable if you keep your obsession leashed."

I looked up at the ceiling. The veins glowed, dim and steady, like a giant sleeping under miles of stone.

"Leashed," I repeated.

Kravius lived. He had many throats. I would cut one tomorrow and the next the day after. I could be patient. Silence is patient. It doesn't rush to fill a room. It waits for the room to notice it was already there.

"Sleep," I told them.

They dispersed. Even in Hell, sleep comes if you hold it by the neck and refuse to let it run. I stayed a while longer, hand on the gauntlet, listening to Noa count the fading heartbeats of the day.

When I finally turned away, the Black Spire stood like a judge who had given his verdict and found it pleasing. The magma ropes whispered to each other in a language of bubbles and heat. Somewhere far above, a bell that was not a bell failed to ring.

I smiled into the old dark.

"Soon," I said.