Nobody could kill the Demon King. Fūin-ō, the first of all demons, the one every other demon came from. Humanity threw a whole generation of its best fighters at him and it wasn't enough. So the first slayers did the one thing left to them: they buried him under a mountain and locked him down with a hundred spirit-seals, each one set inside a stone monument built to carry the weight.
You can't break those seals. They just wear out. One after another, roughly one a year, the gold on a monument lifts away, the stone goes cold, the pilgrims stop coming, and the valley goes bare.
Eighty-one are gone. Nineteen are left.
And he knows. He's been awake down there the whole time, smiling in the dark, counting with us.
What it looks like now
The sky goes purple at sunset. The ground shakes and the papers don't mention it. Every demon out there can feel the King's pulse getting stronger, and they're not hiding it anymore.
The demons
Bullets and blades don't hurt them, they heal in seconds, and they eat people's life. The young ones are wild animals. The old ones, the Elder Brood, still remember the King's voice, and they can twist the world with Blood Glyphs. Lysandra can freeze the blood in your veins with a snap of her fingers, and she moves through high society like she owns it, because she does. Shizumo has spun her silk across every bell tower in the capital and feels a footstep from miles away.
All of them answer to the Seven Ash-Lords. The only one anyone has seen is Gaisen, the King's old marshal. He has spent eighty-one years doing the one thing a marshal does: building an army. Drilled, ranked, armoured in black iron from the mines under the court, standing in a line that has grown every year for eight decades. It has never marched. Not yet.
And some of them used to be us. AshVane was a slayer once. He drank the black blood of the Elder Brood on purpose, traded his aging body for one of living iron, and now hunts his old comrades to clear the King's path.
The slayers
The people hunting demons work for the most boring office you can imagine: Municipal Pest & Hazard Control. Tell them a giant thing ate your neighbour and they'll write it down as sewer gas. That's on purpose. No panic, no red tape, and the hunters move fast.
Their swords are Dawn-Steel, forged from meteor ore, and every technique they pull with one costs them something. Kuze holds eleven northern villages alone because she's the only slayer alive who can fight in a whiteout: one cut that flares the blade white-hot and turns a blizzard into half a second of daylight. It blinds the demon. It blinds her too. She swings from memory of where it was standing.
Chiyo plays an untouchable noblewoman at parties where old demons feed on aristocrats, with needles and wire blades hidden in her silk. Higana came down a mountain wearing the shadow of the demon that killed everyone else at a sealing; it eats the light around her face, it never comes off, and it lets her see in the dark and hear a heartbeat through a wall. Kanae is the one they send when a slayer turns. She has closed forty-one of them, trained nine of them herself, and never asked to be moved.
