- Y/n Tsugikuni -

Chapter 12 - Borrowed Time -

Tanjiro lunged toward the demon. Flames raced down his blade as he cut through the incoming wave of obi.

“Burning Bones, Summer Sun!”

Daki flinched. Her attack was sliced clean through. A searing pain tore through her body, her regeneration slowed. “Eh…?” she gasped, stunned that her technique was breached. She retaliated with a flurry of slashes, but Tanjiro met every strike, faster and sharper than before.

She jumped to a distant rooftop, trying to gain space. But someone was already there.

Not Tanjiro—Y/n.

From Tanjiro’s view, he had only just reached the rooftop. He stopped short, surprised. “Tsugi-san?”

Y/n stood still, sword low, breathing shallow. “Too elastic… Hard to cut through... But why do I feel so weak?” His chest ached. His heart wasn’t beating normally.

Before he could steady himself, Daki struck again. Her sashes knocked both of them down, giving her time to regenerate.

“You’re not getting away, you little shits!” she hissed, launching thirteen more obi tendrils.

Tanjiro set his stance. Y/n slipped into breathing form, though his lungs burned.

“There’s thirteen of them. If I dodge it, the buildings will take the hit…” Y/n muttered. “But why does it feel so fast?”

Tanjiro exhaled. “Why does it feel so slow?”

Y/n’s Slayer Mark had surfaced again—glowing faintly, distorting his sense of time. But unlike others, it weakened him. His body couldn’t keep up with what his mind perceived. Each breath drained him faster. Both slayers intercepted the obi, pinning them to the ground. Tanjiro held steady. Y/n coughed up blood.

‘I’m getting weaker…’

‘I’m getting stronger?’

Tanjiro pushed forward, slicing through Daki’s remaining sashes in a single fluid motion. Her reaction came too late. His blade neared her neck—but his knees buckled. He collapsed, breath ragged. He’d forgotten to maintain his breathing form.

‘I take it back… it hurts just to breathe…’

Daki approached him slowly. “Of course. That’s how it always ends.” She raised her hand. “I’ll take your head off after I—”

Y/n crashed down from above, blade swinging. He just missed. Daki recoiled. All three of them fell through the weakened roof.

Absolutely. Here's a rewritten version with steadier pacing, more detail on emotion, environment, and action, while staying faithful to each character's personality:

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Another shockwave shattered the quiet. Rubble scattered as Nezuko, feral and uncontrolled, burst through the ceiling above. Her eyes glowed with fury, body crackling with demonic energy.

Y/n looked up just in time to shift his weight, narrowly dodging her clawed descent. His body staggered. He didn't have time to draw breath—just instinct. In one smooth motion, he drove the scabbard of his sword between her jaws, wedging it in like a muzzle.

“Nezuko,” he whispered, unsure if he was calling out to her or reminding himself who she was.

His hands trembled. The mark on his chest pulsed—widening, flaring. The medicine coursing through his veins had run thin, and now it was gone entirely. His limbs felt detached. Like every motion demanded more than he had left.

Nezuko thrashed against the scabbard. Her snarl vibrated through the room. Her body was losing shape—regenerating too fast, shifting unpredictably.

Tanjiro stirred. His breath caught when he saw her. “Nezuko!” He stumbled to his feet, alarmed.