The silence in the Zen'in Clan's training grounds was thick, dense like the air before a storm. The sun barely peeked over the walls of the complex, tinting gold the floors worn by countless generations of exorcists. There, alone, Naoya breathed slowly.
He wore light clothing, his torso bare, revealing a young but toned body, hardened by training. He wore no bandages or protection. He didn't need them. Not this time. This time, he wasn't training to win a fight... but to avoid losing his life.
"I grew complacent," he muttered to himself, studying his own hands. "I let myself be carried away by what was easy... by what was weak."
He had been strong. Stronger than the other boys. Stronger than some adults. Even more than some official shamans. His new technique, inspired by Hit and the time jump, gave him a clear advantage. He had mastered speed, cruelty, precision. But Naobito's recent decision had shaken him more than he cared to admit.
A special-rank cursed spirit.
Before he turned 18.
He was 14 years old. And he knew very well what that kind of creature meant. They weren't like Level 3s, or even Level 2s. They were monsters. Real ones. Like the ones that hid when Satoru Gojo walked.
"A time jump won't be enough," he growled, closing his eyes. "Speed won't be enough."
He'd known it from the moment they announced it. He'd felt a pang... not of fear, but of reality. A special level required special-level techniques. Even monsters like Sukuna or Toji Fushiguro had required more than brute force.
"Domain Expansion..." he whispered. And the name of their technique echoed in his mind:
Time Cell Moon Palace.
So far, he'd used it in limited ways. He had activated it fully only once, in simulated training. But never in real combat. He didn't master the details. He didn't understand all the limits. And that, to him, was unforgivable.
"What kind of king doesn't know his own palace?"
The ground in front of him shook as he released cursed energy. It wasn't an explosion, but a controlled outpouring. Precise. Planned. He began to form the seal with his fingers, his mind focusing.
"Domain... expansion..."
The space around him distorted, as if reality itself had become liquid. The sky curved, the ground buckled upward. A pale, gray aura began to envelop him like a lunar mist. Then, with a roar of power, the world changed.
Time Cell Moon Palace.
Everything went dark, save for the enormous white moon above. A prison without bars. A world suspended in a false time flow, controlled by him. His technique didn't just affect time: it created an illusion of altered time. Every second in his domain could become a time lock, trapping the enemy in a loop or accelerating them so their body aged in minutes.
But so far, he'd only kept it active for a few seconds.
"I want to see the limit," he said quietly.
And he ran.
He moved within his own domain, like a fish in water. He marked lines with cursed energy, drawing time traps. He tested what would happen if he accelerated one area. If he slowed another. If he mixed the two. His mind worked with surgical precision.
Every mistake he felt on his skin. A poorly placed loop left him trapped for 1.2 seconds, repeating the same step without moving forward. A timing error left him half a meter outside the limit. It enraged him.
"This is unacceptable!" he roared.
He tried again.
Again and again.
For hours.
Until the blood trickled down his nose, until his muscles trembled. Sometimes his energy was half gone. Sometimes his control collapsed unintentionally. But he kept going.
Because he understood something others didn't.
The world doesn't forgive the arrogant who slumbers.
It was no longer enough to be faster than others. His Hit-inspired technique was no longer enough. Nor was his arrogance, nor his sharp words. If he failed, he would die. Not by noble hands or worthy rivals, but by a cursed creature without conscience or glory. A stupid death.
No. He wouldn't allow it.
"My domain must be perfect..." he gasped. "It must be a perfect prison... an elegant punishment... an inevitable execution."
He felt his technique begin to stabilize. Timelines no longer crisscrossed erratically. The moon of his domain no longer flickered. The time cells turned like clockworks. It was a mechanism, not an aberration.
"If I ever perfect it..." he smiled cruelly. "Not even Gojo will be able to laugh. He has his 'Infinity'... but mine is a palace."
A palace of time.
A cage with moons as witnesses.
An inevitable sentence.
He fell to his knees, exhausted. The expansion slowly dissipated. He returned to the real world. The sun was already high. His body was sweating, wounded, exhausted.
But there was satisfaction on his face. He hadn't completely mastered the "Time Cell Moon Palace," but he had taken another step. A big one.
And above all, he no longer felt complacent.
He felt hungry.
"The elders think I'm a tool..." he whispered contemptuously. "Naobito wants to test me..."
He looked up at the sky.
"Very well. I'll give them a show."