Akaza sank into his stance, muscles tightening like coiled steel. His voice roared across the clearing.
"Destructive Death!"
Akaza's roar tore through the air as his arms blurred faster than sight.
"Disorder!"
Dozens of punches erupted from him at once, each strike powerful enough to shatter stone. Invisible shockwaves screamed outward, slicing through trees like blades of compressed air, all converging on Akira.
Akira didn't really have any formal techniques to counter that kind of assault. All he could do was rely on his Mystic Eyes and his incredible speed to evade the oncoming storm of invisible strikes.
But even with that, several attacks still landed, their impact cracking bones with each hit. For any normal person, the pain must have been unbearable, but Akira had endured far worse. He had been trained to keep on fighting despite the pain ever since he was little, so he completely ignored it and continued dodging.
As the barrage ended, Akira steadied his breath and looked around, only to realize Akaza had vanished.
A sudden chill ran up his spine. He glanced upward instinctively, just in time to see Akaza suspended in midair, muscles coiled, as he prepared to attack.
"Destructive Death: Crushing Type — Ten Thousand Leaves Flashing Willow!"
Akaza's arm came down like the hammer of a god. The blow struck the earth with a sound that split the heavens. The ground beneath him exploded, shockwaves rippling outward in a blinding flash of light and dust. Stone and soil were thrown skyward in violent bursts as the forest trembled.
Akira was thrown back by the impact but quickly twisted midair, landing on his feet and regaining balance.
But before he could even draw another breath, Akaza attacked again without pause.
"Destructive Death: Air Type!"
Akaza punched and kicked the air, launching invisible blades of compressed shockwaves straight at him. Akira was forced back onto the defensive again, weaving through the invisible onslaught.
By the way, for some reason, the music playing in the system suddenly changed.
Now, blaring through the battlefield was.
[Kimetsu no Yaiba: Mugen Train M36-1 – Rengoku vs Akaza Theme.]
Akira, still dodging a storm of invisible shockwaves, shouted telepathically, "Sister, what the hell?! Why are you playing his theme!?"
Selena's voice echoed in his mind, giggling. "Sorry, brother~ but I just had to! I couldn't help it!"
Meanwhile, the spectators were just as bewildered.
"Oi! Where the hell is that sound coming from!?" Inosuke yelled, looking around in confusion.
Erika sighed, resting her hand on her forehead. "He's probably… playing it using magic," she muttered, clearly used to Akira's antics.
Tanjiro tilted his head. "Why, though?"
"He probably thinks it looks cool," Erika answered flatly.
Rengoku, watching the fight closely, narrowed his eyes. "He's being pushed back," he said gravely. "But why isn't he using his armor or his magic to fight?"
Erika shook her head softly. "He probably doesn't want Muzan to learn about his powers. That's why he's not even healing."
Tanjiro clenched his fists. "But he's being pushed back! We should help him!"
"Yeah!" Inosuke added, gripping his dual blades. "Let's charge in and…"
Rengoku stopped them with a firm voice. "No. We can't recklessly rush in. We must wait for the perfect moment to strike."
Both Tanjiro and Inosuke froze, understanding the weight behind his tone.
While the others prepared to intervene, Erika stayed silent.
She knew Akira wasn't truly in danger; he hadn't even used his armor or his evolution powers, but that didn't stop her from worrying.
He hadn't developed any special offensive techniques yet, and even when his blows landed, Akaza's regeneration erased them instantly.
So for now, Akira was on the defensive. And though she knew he was smart enough to fight back, Erika still couldn't help but feel unease.
Her feelings were a tangled mixture of worry and trust.
Even so, she prepared herself mentally. If things went truly out of control… she would jump in without hesitation.
Back to the fight.
Akaza was still launching long-range shockwave attacks using his Air Type, each strike cutting the wind like a blade.
Akira continued to dodge with sharp precision, his movements a blur of instinct and calculation.
"Hahaha!" Akaza laughed, his voice ringing with excitement. "As I thought, you have to become a demon after all, Akira! Let's fight each other for all eternity!"
Akira was too busy dodging to respond, but if he could, he would've probably called him a creep again.
But Akaza continued, his words overflowing with twisted admiration.
"Become a demon, Akira! You're strong, one of the chosen ones!"
Before Akira could respond, one of the invisible shockwaves caught him off guard, striking his side and throwing him back through the dirt.
Akaza stopped his attacks for a moment, watching.
Akira slowly got back on his feet, breathing heavily. Blood trickled from cuts across his arms and cheek. The continuous strain of Star Breathing was beginning to take its toll on his body. He was hurt, his stamina dropping—and yet, he refused to heal.
He was also actively suppressing his healing factor.
Because if Muzan ever found out about a human capable of such rapid recovery… it would be too dangerous. Far too soon for that.
Akaza smirked. "Even if you fight to the death, you can't win, Akira. Struggle all you want, but a human can never defeat a demon."
Akira smirked, wiping the blood from his lip. "All that talk, and you still haven't defeated me. If you want to turn me into a demon, then defeat me first."
He dropped into a stance, activating Star Breathing at full effect. The air around him shimmered, pressure radiating outward.
Akaza's grin widened, exhilarated. "What a tremendous fighting spirit… Amazing aura, even with those injuries!"
He laughed maniacally. "HAHAHA, You have to become a demon after all, Akira! I'll beat you here and now, and then I'll make you one!"
Akaza crouched, both arms poised at his sides, energy surging like a storm.
"Destructive Death: Annihilation Type!"
He lunged forward, both palms generating two massive circular shockwaves that roared toward Akira.
For Akira, time slowed.
Everything blurred. His heartbeat, his surroundings, even Akaza's attacks, slowed down to frames of motion.
This wasn't magic. It was the result of his thought acceleration, born from years of brutal training and dying too many times under his mother's hand. Every neuron fired at once, amplifying his focus beyond human limits.
The incoming attack was the strongest one yet. He could dodge it… But he had a better idea.
"Breathing techniques can let humans do the impossible", Akira thought. "Thunder Breathing users can break the sound barrier with their legs… so with Star Breathing, if I use it with my arms, then theoretically I can throw a punch faster than sound".
He'd never done it before, but he knew he could do it.
So he inhaled deeply, steadying himself as he took a stance and thought of one of the attacks he always wanted to use.
Then, as Akaza's twin shockwaves neared, Akira pulled his fist back like a cannon and roared.
"FALCON PUNCH!!!"
His fist shot forward, faster than sound.
The air ignited from sheer speed, forming the silhouette of a blazing flame falcon.
The two attacks collided.
BOOOOOOOOOOOOOOOOM!!!
The world turned white.
Dust and shockwaves erupted in every direction, shaking the ground like an earthquake. Trees bent under the pressure.
Even the spectators, Tanjiro, Inosuke, Erika, and Rengoku, were blown back by the blast, shielding their faces from the storm of debris.
The dust slowly settled.
Both Akaza and Akira stood amidst the destruction.
Akaza's body was battered and torn, cracks spreading across his skin from the sheer force of Akira's last attack, but even that monstrous damage began to heal, albeit more slowly than before.
Akira, on the other hand, was far worse off. His right arm, the one he had used for the Falcon Punch, hung limp and mangled, skin burned and blistered from the shockwave. The smell of scorched flesh mixed with the smoke around him.
Breaking the sound barrier and igniting the air... had taken its toll.
Everything grew silent.
Even the background music from the system had stopped playing.
Tanjiro, Inosuke, Rengoku, and Erika stared, speechless.
Akaza's calm voice broke the silence. "As I said… You can't win, even if you fight to the death, Akira." He smiled coldly. "The damage I took from your magnificent punch has already healed completely. But what about you? Your right arm, shattered. Bones broken. Internal organs damaged. All irreparable."
He spread his arms wide. "If you were a demon, you'd heal in the blink of an eye. Those wounds would be mere scratches."
But Akira only smiled calmly. "Oh, is that so? If demons are that powerful…"
He tilted his head up slightly. "…then can you keep fighting me without running away?"
Akaza froze, confusion flashing across his face.
"What are you…?"
Then realization dawned.
He looked up, and his expression changed completely.
The eastern sky was glowing.
The sun was rising.
"Damn…" Akaza hissed, taking a step back. "Daybreak… already?"
He hadn't even realized it during their battle.
"No… I have to get away!" He turned to flee.
But Akira's voice cut through the dawn. "Heh. You think I'll let you run away?"
Akira's figure blurred as he dashed forward at full speed.
Akaza gritted his teeth. If he fought now, he'd never escape the sun, and with Akira and the others still alive, his odds were grim. He needed to stop all of them here long enough to retreat.
He slammed his foot into the ground.
"Destructive Death!"
The red snowflake pattern of his Compass Needle burst into life beneath him, glowing fiercely before turning a brilliant icy blue.
Twelve energy clones formed, each standing at one point of the snowflake, surrounding Akaza like reflections in shattered glass.
"Final Form—Blue Silver Chaotic Afterglow!"
A barrage of hundreds of shockwaves exploded outward in every direction.
The ground quaked. The forest shattered. The battlefield vanished in light and chaos.
Akira's eyes widened; he hadn't expected Akaza to unleash his final form here.
And Erika and the others were in the blast zone.
He looked over to Erika to see her already using her ribbons, forming a crimson dome of protection around everyone. But Akira knew it wouldn't hold.
He clenched his left fist, the only one still working.
"Fine", he thought. "Guess I'll just have to offset it a little".
At full speed, he appeared before them, raising his uninjured left arm.
He clenched his fist, his body burning from exhaustion, and shouted.
"FALCON PUNCH!!!"
The explosion that followed drowned everything else out.
A roaring flash of light engulfed the battlefield, and the ground trembled beneath their feet.
When the dust finally cleared, the scene was… devastation, the land was unrecognizable, scorched and broken.
But Akaza was nowhere to be seen.
He had escaped.
The first rays of sunlight now illuminated the battlefield.
Erika ran forward, her ribbons retracting as she called out, "Akira! Are you alright!?"
Akira exhaled slowly. "Yeah… I'm fine."
He smiled weakly, but his entire body was trembling, his hands scorched and bleeding.
Erika frowned. "You are definitely not fine."
Akira chuckled weakly. "Don't worry. It's fine."
Slowly, his wounds began to heal, scars closing, skin knitting back together.
Tanjiro, Inosuke, and Rengoku approached, stunned by the destruction around them.
"So that was the power of Upper Moon Three…" Rengoku murmured.
Akira smiled faintly. "Sorry, he escaped."
Rengoku smiled faintly, his fiery spirit undimmed. "Don't apologize, Akira-kun. This is the first time anyone's ever pushed back an Upper Rank demon like that. We'll get him next time."
Tanjiro stepped forward. "Are you really okay, Akira-san?"
Akira replied, "Don't worry, it's just superficial wounds. Look, it's already healing."
And indeed, his wounds were visibly closing… except for his hands, which were charred black from the Falcon Punch, remained untouched.
Erika noticed and frowned. "Why aren't your hands healing?"
Akira flexed his fingers, wincing slightly. "Yeah, well… I kind of burned them badly. Burn wounds are harder to heal. My regeneration isn't that strong; it'll probably take a few days."
Erika looked worried but didn't press further.
Then Tanjiro looked around the destroyed area. "My sword… I can't find my sword!"
Akira tilted his head. "With that last explosion, it's probably...wait."
His eyes widened as he scanned the battlefield.
"Where's my bike?"
He looked around until he spotted it in the distance, completely destroyed.
Akira froze.
Then his expression twisted in pure despair.
"…My bike…"
He fell to his knees, staring at the wreckage in despair.
Lifting his head toward the sky, and screamed into the heavens.
"AKAZA!!! I WILL NEVER FORGIVE YOU!!!"
His voice echoed across the ruined forest and the derailed train near them.
The battle was over… but the price of the battle was more than he imagined.