Chapter 137 Fierce Battle

The strength of Kokushibo is beyond doubt. A guy who can awaken the patterns, traverse the world, and comprehend the Moon Breathing is certainly not an ordinary person.

Even in the entire world of Demon Slayer, he can be considered a very strong warrior. Unfortunately, he shares the same era as Yoriichi Tsugikuni, a being who has not appeared in a thousand years, living in the same time as him.

Kokushibo's difficulty has exceeded what Roa had anticipated.

If he were to only use Thunder Breathing, he definitely wouldn't be able to take down his opponent in a short time.

At this level, the Nichirin Sword is not very effective against Upper Moons.

Therefore, he can only reveal his hidden trump card. In the end, Roa contemplated whether to use Sun Breathing or the Sword of Light and chose Sun Breathing.

It would still be a bit too costly to reveal the Sword of Light now; Sun Breathing is just right.

Basically, as long as he uses Sun Breathing, it will inevitably stimulate two individuals at the same time: one is the guy in front of him, and the other is Muzan Kibutsuji.

Muzan, who was once beaten like a stray dog by Sun Breathing, would definitely not swallow this humiliation. Of course, with his high strength, he would likely choose to flee.

However, as long as Roa hides his strength to the point where he can barely defeat Upper Moon One, Muzan Kibutsuji would definitely not be able to sit still.

He would find a way to deal with Roa, this significant threat. As long as he pretends to be injured and needs some time to recuperate, not to mention Muzan, even he would be unable to resist taking action against someone like that.

So, he might as well use Sun Breathing directly.

At this moment, Roa's breathing rhythm began to change.

The surrounding air seemed to become scorching in an instant. The lightning around Roa's body gradually dissipated, and his Nichirin Sword began to burn. Under Kokushibo's cold gaze, flames enveloped the sword, the intense heat distorting the surrounding air.

Kokushibo stared intently at Roa, his three pairs of golden eyes observing Roa's movements. He murmured, "Is this Flame Breathing? No, this aura… it's not Flame Breathing."

But when Roa raised his hand to grip the sword, Kokushibo's pupils suddenly contracted. His previously calm emotions began to boil over. The figure before him began to overlap with someone from his memories—raising his hand, gripping the sword, breathing—the overwhelming aura, the feeling, reminded Kokushibo of one person.

Yoriichi Tsugikuni!

The man who was born with the Demon Slayer Mark and the Transparent World, the man who lived to his eighties despite activating the Mark, the man who appeared countless times in Kokushibo's dreams!

The figures overlapped, and Kokushibo's emotions could no longer remain as they once were. The intensity of his emotions was so great that even his breathing, which had been steady, momentarily faltered.

"You… no, he's dead, isn't he? You can't be him. He died three hundred years ago. Yes, I saw him die with my own eyes. So, who are you?"

Kokushibo's expression grew increasingly twisted. Though he already looked somewhat terrifying, this was not the limit of his horror.

It was no wonder Kokushibo reacted this way. Yoriichi had become a shadow in his heart.

To live in the same era as such a genius was both a blessing and a curse. Even more tragic was that this genius was his younger brother.

Kokushibo was not a good person, but neither was he entirely evil.

He had extended a helping hand to his brother when he was in need, but as Yoriichi continued to display his overwhelming strength, jealousy gradually consumed Kokushibo.

Yoriichi was like a nightmare in Kokushibo's life. He constantly thought about how to surpass him.

The achievements he dreamed of were effortlessly attained by Yoriichi, only to be casually abandoned by him.

Kokushibo could not understand Yoriichi, nor could he become a swordsman as powerful as him.

They had been separated for ten years, and when they met again, Yoriichi had grown into a strong, flawless man with a noble character.

An insurmountable mountain.

"Damn it! Yoriichi, you should have died! Why were you born in the same era as me!"

Kokushibo's six eyes were now fully open, and he gripped his grotesque katana tightly.

He closed the distance and unleashed his strongest sword technique.

"Sixteenth Form: Moonbow, Half Moon!"

He raised his katana high and then brought it down with tremendous force. The slash transformed into a crescent-shaped sword that surged toward Roa.

The ferocity of the attack was unprecedented, and the crescent-shaped swords almost completely enveloped the space around Roa.

Roa expressionlessly raised his hand.

Then came the sound of intense breathing. His heart began to beat rapidly, pumping large amounts of blood and causing his body temperature to rise sharply.

The rapidly increasing temperature caused the Nichirin Sword to take on a crimson hue.

This was the Red Sword!

"Fourth Form: Fake Rainbow!"

The Red Sword, carrying terrifying heat, surged forward. Roa's figure vanished like a bubble.

Kokushibo's six eyes opened wide, and he activated the Transparent World to its fullest extent. In an instant, Roa's figure was revealed.

Kokushibo narrowed his eyes and murmured, "An illusion? Seventh Form: Mirror of Misfortune, Moonlit."

He pressed down with his katana, which had now undergone a dramatic transformation. The sword, originally grotesque, now had two additional sections, making it even more bizarre.

Three more ferocious slashes were unleashed, this time even faster than before.

But even as the slashes collided with Roa, his figure vanished like a bubble.

As Kokushibo had said, it was just an illusion.

"But with such a wide range of attacks, where can you hide?"

In the next moment, a towering flame erupted, and the red blaze instantly exploded, the heat wave scorching the surrounding air.

"Fifth Form: Fire Wheel!"

The sound of intense breathing filled the air. Roa's figure flipped in mid-air, and the Red Sword, wreathed in flames, descended in a vertical arc toward Kokushibo's neck.

Kokushibo's pupils contracted. Even with the Transparent World, he could no longer track Roa's movements. He had no idea how Roa had dodged the dense barrage of slashes.

"Eighth Form: Moon-Dragon Ringtail!"

In a desperate move, Kokushibo swung his katana with all his might. The force behind the slash was comparable to Thunder Breathing's First Form.

The powerful slash destroyed everything in its path, the immense force surging toward Roa.

But if Kokushibo was domineering, Roa was even more so. He charged forward head-on, his crimson-gold eyes reflecting Kokushibo's figure. His long hair scattered in the wind as the two massive slashes collided.

But the moment Kokushibo's katana clashed with Roa's Red Sword, it shattered into two pieces. The eyes covering the sword writhed in agony, a sight that would make anyone with trypophobia shudder.

The severed section of the sword was scorched by the intense flames. Kokushibo frowned—the heat of the slash had significantly slowed the sword's regeneration.

But even so, it was still far from matching that man.

Even though Roa had shattered Kokushibo's katana, the crescent-shaped swords instantly erupted.

But as they erupted, they were engulfed by the towering flames and dissipated into nothingness.

The exchange between the two lasted only a moment, but in that instant, the roles of attacker and defender had shifted.

At such close range, Roa calmly took a deep breath, gripping the Red Sword in a reverse grip, and focused all his energy into a single point.

"Sixth Form: Burning Bones, Summer Sun!"

Without pause, after the Fifth Form, Roa seamlessly transitioned into the Sixth Form.

If this slash hit Kokushibo's head, Roa was confident it would turn him to ash.

Meanwhile, Roa's blood surged, and his magic began to flow through his body. The Dragon Blood within him awakened.

Blood Rage! First Stage.

Although his magic was limited, the restrictions on his innate abilities were not as severe as he had imagined.

In this instant, Roa's muscle density underwent a dramatic change, and his internal organs were strengthened by his magic. Suddenly, Roa's speed increased yet again.

The scorching Red Sword transformed into flames as it slashed toward Kokushibo's neck. Kokushibo retreated rapidly, but even before the sword could reach his neck, the heat from the Red Sword was already unbearable.

In the face of death, there is great terror. Sensing Roa's overwhelming killing intent, Kokushibo wasted no time and turned into a blur as he retreated.

But Roa wouldn't let Kokushibo escape so easily. The flames at the tip of his sword surged forward like a tidal wave, engulfing Kokushibo.

Kokushibo had no choice but to raise his katana in an attempt to block.

Originally, Kokushibo could have intentionally let Roa shatter his sword, relying on his immortality to trade injuries and wear Roa down.

But judging from the current situation, if he took this slash, he wouldn't be able to recover in a short time.

"Damn it! Yoriichi, even in death, you're still causing me trouble!" Kokushibo roared in anger.

Roa couldn't help but laugh at Kokushibo's words. His movements remained swift and precise. Despite Kokushibo's current embarresment, he still had a trick up his sleeve.

"Seventh Form: Sunflower Thrust Form!"

Roa raised the Red Sword horizontally, and flames encircled the sword. He thrust the sword toward Kokushibo's heart with tremendous force.

The Red Sword, combined with Roa's incredible speed, pierced through Kokushibo's body in an instant. This time, there was no way for Kokushibo to dodge.

Kokushibo's eyes widened in fury. The moment he was struck, blood gushed out, and his shattered katana was instantly restored.

Kokushibo growled, "You think this is over? Brat? First Form: Dark Moon, Evening Palace!"

He flipped his katana and slashed fiercely at Roa.

Roa had intended to take some damage, but such an obvious move was not worth it. He pulled out the Red Sword and blocked the slash, then kicked Kokushibo away.

This time, Kokushibo's face turned pale. He felt an intense burning sensation spreading through his abdomen, and the speed of his cell regeneration was drastically reduced.

"Damn it!" Kokushibo climbed to his feet, a gaping hole in his chest. His once pristine kimono was now tattered.

He took a deep breath, his mind racing to find a solution.

Although Roa's strength was not as overwhelming as Yoriichi's, Kokushibo had to admit that if the battle continued like this, he was at risk of dying.

Should he flee?

The moment this thought crossed his mind, Kokushibo immediately dismissed it.

He couldn't run, at least not this time. He couldn't lose to him again.

He took a deep breath. Even though his regeneration had slowed, it was still recovering at a visible rate.

The damage from the Red Sword was terrifying, but Roa hadn't revealed all his cards yet. He had held back slightly with his Sun Breathing.

But even so, Sun Breathing was still a nightmare for Kokushibo.

Kokushibo's right hand, gripping the katana, trembled slightly. Suddenly, he retreated again.

Roa raised an eyebrow. Though he didn't know what Kokushibo was up to, he wouldn't let him have his way. He followed closely, his figure like a shadow.

"Fourteenth Form: Catastrophe, Tenman Crescent Moon!"

This technique unleashed overlapping, swirling slashes with a wide range and considerable power, but to Roa, it was still too simplistic.

Roa charged forward expressionlessly, his Red Sword cutting through the slashes.

Then came—

"Tenth Form: Drilling Slashes, Moon Through Bamboo Leaves!"

"Ninth Form: Waning Moonswaths!"

"Sixteenth Form: Moonbow, Half Moon!"

Kokushibo's attacks were fast, and each one was a long-range strike. The crescent-shaped swords from Moon Breathing rained down like a storm, surging toward Roa.

Roa raised an eyebrow. Kokushibo's tactics had caught him slightly off guard.

If Kokushibo intended to drag out the battle like this, an ordinary person would have no chance.

After all, the human body was too fragile. A few hits from these crescent swords would cause severe bleeding, and under such a dense barrage, no one could last more than a few moments.

But Roa's Sun Breathing could easily cut through all these slashes.

"Fourth Form: Fake Rainbow!"

Roa's figure vanished like a bubble once again. Kokushibo narrowed his eyes, but even with the Transparent World, all he could see was Roa's afterimage.

Unable to locate Roa, Kokushibo gripped his katana and unleashed a continuous barrage of slashes. Since he couldn't find Roa, he simply turned the surrounding area into his attack zone. The ground was torn apart, and the forest now looked like it had been through a war. The word "pockmarked" couldn't even begin to describe the devastation.

But even so, he still couldn't locate Roa.

Again, Kokushibo gritted his teeth in frustration. Damn it.

"Ninth Form: Setting Sun Transformation!"

A cold voice came from the distance.

Roa's figure was nowhere to be seen, but a spark of flame appeared in the distance. In the blink of an eye, the flame grew into a blazing inferno, taking the shape of a dragon. The dragon's head emerged from the apocalyptic scene, and then, as if flying through the air, it streaked across the sky with incredible speed.

The dragon surged forward, crossing dozens of meters in an instant, charging toward Kokushibo.

At the same time, Kokushibo's lips curled into a crazed smile. He murmured, "Yoriichi, let's see who will emerge victorious!"

The dragon, carrying scorching heat, left a trail of flames in its wake. Roa, wielding the Red Sword, charged toward Kokushibo.

The flames surrounding the Red Sword formed the dragon's head, slashing toward Kokushibo's neck.

But Kokushibo's body suddenly transformed. Swords sprouted from his body, and in that instant, crescent-shaped slashes erupted from the swords.

But Kokushibo's plan to go all out was matched by Roa.

Without slowing down, Roa's Red Sword slashed toward Kokushibo's neck.

Even as his head was severed, Kokushibo's expression remained twisted with a crazed smile.

The Red Sword burned with intense flames, and the crescent-shaped swords rained down on Roa like a storm.

Kokushibo's plan was to trade his head for Roa's life.

His scheme was clear, and Roa saw through it. He tightened his grip on the Nichirin Sword, the immense force severing Kokushibo's head. Where the sword passed, the neck turned to blackened ash.

At the moment when Roa slashed at the neck, the sword formed by the body of Kokushibo lunged towards Roa.

In an instant, the crescent-shaped sword had already pierced towards Roa's body.

To protect himself, Roa enveloped his entire body with magical energy, and the muscle density caused by the dragon blood tightened, directly withstanding the damage from the first wave of the crescent sword. Several bloodstains instantly appeared on Roa's body, with large areas of bleeding. However, these were only caused by the rupture of capillaries, which looked terrifying but were actually minor issues as long as no internal organs were injured.

Of course, this was only the first wave of the attack, but the first wave also managed to hit Kokushibo.

Roa thrust the crimson sword in his hand, and with the enhancement of the Transparent World, he swiftly pierced through Kokushibo's heart.

With his heart pierced and his head severed, even an Upper Moon should be dead, right?

Golden blood dripped onto the ground, and Kokushibo's severed head looked up at the night sky.

"Lost again? Lost to you again," Kokushibo murmured softly.

In the final moments of his life as a demon, he still remembered that person, his lifelong nemesis.

Roa didn't say much. He pulled out the crimson sword that had pierced through Kokushibo. To Roa's surprise, Kokushibo was unexpectedly calm before disappearing.