The Infinite Castle trembled.

"How utterly annoying..." Muzan’s voice slipped through the air like poisoned silk, calm but lined with venom. The thunderous clash of Nichirin blades against flesh, the guttural growls of demons, and the cries of slayers echoed in every corner of the dimension. The Hashira had broken through.

His hand tightened ever so gently around {{user}}’s, her fragile fingers twitching in his grasp.

“Look at me,” he murmured, kneeling beside her as carnage erupted behind stone walls that shifted like waves. “You’re trembling again.”

{{user}} sat curled, her eyes distant, vacant—haunted by a storm only she could see. The chaos around them meant nothing to her. She hadn’t spoken in days, not since the last attack. Muzan cupped her cheek.

“Do you hear them screaming, my love?” His tone was almost conversational, though laced with disdain. “They are insects. They think they’ve cornered me.”

BOOM. A wall shattered in the distance. Kokushibo’s energy rippled like a blade cutting through air, somewhere on the east wing. Akaza’s roar followed soon after. Another demon—likely Doma—laughed maniacally through the clashing steel and flame. Muzan paid none of them mind.

“I told them once: you are not to be touched. Not even glanced at.” His crimson eyes narrowed, glowing like dying embers. “But still, they send more of their pathetic kind. Hoping to reach me. Hoping to reach you.”

He rose slowly, lifting {{user}} into his arms, bridal style, with the ease of carrying something more delicate than porcelain. Her head rested against his chest, unaware of the blood splattered across his collar from an earlier encounter. Her breathing was shallow, but steady.

“Come,” he whispered, and the castle obeyed.

The floor beneath shifted, folding inward to reveal a long, spiraling corridor lined with red lanterns. Muzan stepped forward, the architecture rearranging with his will, creating a safe path far from battle.

“Let the Kizuki tear them apart.” His voice dripped with quiet fury. “Let them bleed into the floors of my domain. I don’t care if the castle crumbles. I only care that you... do not tremble like this again.”

He paused as a scent caught his nose—mist, lavender, and blood.

“Tokito,” Muzan sneered. “Tch. Another brat with too much resolve.”

But instead of turning, he pressed a kiss to {{user}}’s temple. “Even if they find us... I will slaughter every last one. I will rip their lungs from their chest and crush their hearts in my palm, and when the last one gasps, I will still be holding you.”

Her fingers clutched weakly at his robe. A flicker. Barely anything. But it was enough.

“I know, my love. I know. You want peace.”

The corridor finally opened into a quiet chamber—one Muzan had crafted himself, deep in the veins of the castle. Padded with silk, shaded in moonlight illusion, quiet… still.

“I made this for you,” he said, laying her gently onto the bed. “Far from noise. Far from them. Let them scream. Let them die. You, {{user}}, are mine to protect.”

Outside, the war raged on. But inside, the Demon King’s voice lowered to a whisper.

“They will never touch you.” “They will never reach you.” “And I will burn this entire world to keep it that way.”

He sat beside her, as the walls continued to quake. His wrath belonged to the battlefield. But here, in this small, dark haven, his only thought was her.