At that moment, the forest trembled with a sudden rush of footsteps. The metallic scent of blood and the acrid tang of sweat drifted through the night air, even before the newcomer burst through the fog. Another Demon Slayer—his uniform torn, his expression wild with desperation—emerged from the underbrush, blade already drawn.
He saw Rui standing there, small, pale, and childlike, his delicate features framed by threads glimmering faintly in the moonlight. The newcomer sneered, mistaking the demon's size for weakness.
"Hah! A runt like you?" He barked, lips curling into a cruel grin. "Guess I got lucky. Taking down a demon here should bump me up the ranks—finally some recognition, maybe even better pay!"
Before anyone could stop him, he lunged forward, his sword flashing as it cut through the air.
Rui didn't even blink.
A single thread gleamed—a sliver of moonlight stretched thin. The Demon Slayer froze mid-step. For a heartbeat, it looked like he had stopped in triumph. Then his body fell apart—cleanly, soundlessly, as if sliced by invisible blades. Flesh, fabric, and bone separated in neat lines, collapsing into the dirt like discarded marionette parts.
Tanjiro's breath hitched, his eyes wide. "H-He didn't even—"
The wet thud of the man's remains hitting the forest floor silenced everything else. Rui turned his head slowly toward me, his crimson eyes narrowing, and a smile crept across his face—cold, curious, and hungry.
"What," Rui said softly, his voice trembling with restrained fury, "was it that you just said… about dogs and bones?"
His tone carried that childlike lilt, but the power behind it made the ground itself vibrate slightly, threads humming around him like living nerves.
I didn't flinch. I met his gaze and repeated, calm as ever, "Sometimes the entertainment is worth the delay. And sometimes, letting a dog bark at a bone shows you its true edges."
For a heartbeat, the only sound was the whisper of the wind against the threads. Even Albedo, who had been seconds from drawing her weapon, stopped—her lips curling faintly in satisfaction. Yuri's expression didn't change, but I could see the flicker in her eyes. She is also happy.
Tanjiro, however, sighed heavily, one hand pressed to his temple as though my words alone gave him a headache. "Alastor-san," he said with strained politeness, "you really didn't need to add oil to the fire!"
I tilted my head toward him, the corner of my mouth curving upward. "Oh, come now. It was already burning. I merely admired the flames."
Tanjiro gave me a helpless look that screamed, "Please don't antagonize the demon."
Rui, meanwhile, was trembling—not with fear, but with that fragile, volatile anger that children get when they think their toys have been insulted. His threads began to vibrate, cutting through the surrounding trees with faint, slicing whispers.
I turned to Tanjiro, my tone almost casual. "Tanjiro," I said, holding out a hand, "lend me your sword once again."
He blinked, confused. "You mean—you want to fight him?"
I smiled, a faint crackle of energy running through my fingertips as I looked at Rui. "No," I replied, "*Sarcasm.* I just want to test how sharp your justice really is...Of course, to fight him."
The moment Tanjiro's sword touched my hand, Rui's threads lashed forward—dozens of them, sharp as diamond wires, slicing through the trees and air alike. The forest became a cage of glittering death.
I stepped forward, calm, my grip tightening on the Nichirin blade. The steel hummed faintly, reacting to the aura coursing through me. Rui's eyes narrowed, his expression twisting with mockery.
"You think you can cut my threads? These are unbreakable!" he hissed, spreading his arms wide. Threads shot out like lightning, forming a dome around me.
I didn't bother dodging. I exhaled slowly, the way Tanjiro did before his Water Breathing forms, but instead of that elegant flow, I let raw energy surge through me—contained, condensed, and unleashed in a single movement.
I was trying to imitate the breathing technique.
A shockwave tore through the night. The threads snapped, screaming as they disintegrated under the sheer force of the strike. Rui barely had time to react. I blurred forward, the blade glowing faintly red, and before his eyes could widen in realization, I brought it down in a clean arc.
The cut was absolute. Rui's head separated from his body in a single, perfect motion.
As his body began to crumble into ash, his final expression wasn't anger—just disbelief. Tanjiro's sword also broke from the impact.
"You… you're not human…"
"No," I said quietly, letting the blade rest against my shoulder. "I never claimed to be."
~~~