Sun Breathing

*Ding—ling—*

Suddenly, the sound of wind chimes could be heard.

Somewhat distant, yet also strangely close.

*Ding—ling—* *Ding—ling—*

The rhythmic tinkling of the wind chimes seemed to stir and call out to Riezel, it sounded pleasant and captivating.

In a daze, Riezel followed the sound of the wind chimes, slowly walking in a particular direction.

"Wait a sec... Where the hell is this...?"

As Riezel snapped back to reality, his mind emerging from the haze, he suddenly realized he was in an utterly unfamiliar place.

"Mountaintop?"

Indeed, Riezel found himself atop a mountain.

It was a seemingly lofty peak, almost touching the sky, bathed entirely in the sunlight, making the sun appear larger than it actually was.

"How did I end up here?" Riezel frowned.

Wasn't he on the Mugen Train just a moment ago?

One second he was getting his ticket checked by the conductor, and the next moment he was in a place like this.

"Don't tell me I get hypnotized... Is this inside a dream?"

Realizing what had happened, Riezel felt a twinge of amazement.

He, with the highest rank of Abnormal Resistance development ability and immunity to mental interference from Self Redemption, got hypnotized by a demon?

He couldn't believe it.

Yet, the undeniable reality before him told him that whether he believed it or not, he had indeed entered a dream.

The evidence was clear—despite being on the mountaintop with strong winds and intense sunlight, he couldn't feel the breeze brushing against his body, nor could he sense the warmth of the sun.

"Fascinating..."

Confirming this, Riezel murmured to himself.

After observing his surroundings for a moment, Riezel quickly reached out his hand and grabbed his own neck, preparing to snap it.

This was the most effective way to break free from the demon's dream—killing oneself in the dream would lead to waking up.

However, just as Riezel was about to snap his own neck, a deep voice suddenly reached his ears.

"Sun Breathing consists of thirteen sword forms."

When this unexpected voice echoed in his ears, Riezel's movement to snap his neck halted. It was only then that he noticed he wasn't alone on this mountaintop.

Seemingly out of nowhere, a figure of a man appeared not far from him, facing away, exuding a mysterious aura.

He had black hair tied up in a high ponytail with red edges, dressed in a red haori, holding a sword in hand, and standing against the backdrop of the sun in the sky.

*Ding—ling—*

The familiar chimes sounded again, but this time it came from the earrings of the mysterious man—no, mysterious swordsman.

On the swordsman's ears were a pair of hanafuda earrings with sun symbols. When one looked carefully, these earrings were undoubtedly identical to the ones Tanjirou wore on his ears.

"You..."

Riezel paused his words, staring at the swordsman standing before him, facing the sun, unable to move.

"Huuu... Haaa..."

In the next moment, the swordsman began to breathe in and out without any apparent reason.

Taking in large amounts of air, the swordsman maintained his position with his back to Riezel and began demonstrating a strange breathing technique right in front of him.

Clearly, this breathing resembled Kyoujurou's Flame Breathing in some ways, yet it was entirely different.

Kyoujurou's breathing was powerful, with each exhale bringing a faint sensation of heat as if breathing out flames rather than air.

While the breathing of this swordsman indeed felt similar to Kyoujurou's Flame Breathing—powerful and emitting a slight heat like flames—compared to his Flame Breathing, this swordsman's breath not only carried the burning and destructive power of flames but also a sense of endless energy.

As the swordsman breathed toward the sun, the mysterious aura emanating from him intensified, as if he were no longer human but had transformed into a spirit.

Like a spirit, the unknown swordsman began to dance.

"Sun Breathing - First Form - Dance."

With a faint whisper, the swordsman released a slash forward.

*Swish!*

It was an arcing slash.

His slash was swift, appearing like a fleeting ray of sunlight. As it cut through the air, flames suddenly ignited, forming the trajectory of a sun, slicing through the void and the atmosphere.

"Sun Breathing - Second Form - Clear Blue Sky."

The swordsman smoothly transitioned into the next attack, his sword turning naturally.

Leaping high into the air, he twisted his body and brought down the flaming sword from above, carving another sun trajectory. As it slashed onto the ground, the flames transformed into a flaming wheel, spreading out in all directions.

Wherever the flaming wheel passed, everything was scorched by the flames, leaving behind charred marks and terrifying sword scars that seemed capable of cleaving the entire mountaintop, displaying astonishing power.

In this manner, the swordsman continued to dance, repeatedly showcasing his swordsmanship.

"Raging Sun."

"Fake Rainbow."

"Fire Wheel."

"Burning Bones, Summer Sun."

"Sunflower Thrust."

"Solar Heat Haze."

"Setting Sun Transformation."

"Beneficent Radiance."

"Sun Halo Dragon Head Dance."

"Flame Dance."

Each dance represented a sword form.

Each slash represented a sword technique.

The swordsman repeatedly practiced these twelve sword forms, facing the sun, with his back to Riezel, enveloped in flames, dancing like a flame spirit.

No.

He was not a flame spirit, but a sun spirit.

Riezel began to feel a sense of illusion as if this swordsman had flown out from the rising sun he faced, even though flames were rolling around his body, but wherever his sword passed, it seemed capable of cutting through the air, the earth, everything, burning all existence, yet strangely, it didn't evoke fear but rather a marvelous sense of closeness to nature and a mysterious captivated feeling.

It wasn't flames that destroyed everything, but a radiant flame that expelled every evil.

It wasn't just high temperatures that evaporated matter, but a holy light that purified vile darkness.

"Huuu... Haaa..."

As the swordsman danced amidst the billowing flames, he continuously unleashed sharp and powerful swordsmanship while breathing rhythmically.

Although the breaths were not very pronounced, they echoed distinctly in Riezel's ears, allowing him to directly feel the intricacies of this breathing.

Watching all this, feeling all this, unknowingly, Riezel slowly released his hand from his neck.

He immersed himself in the swordsman's sword dance.

He was deeply attracted by the swordsmanship practiced by the swordsman, unable to look away, unable to remember anything else.

Every slash, every sword form wielded by the swordsman, resembling the sun spirit, deeply imprinted in Riezel's mind, imprinted deep in his heart, making him unable to forget no matter how hard he tried.

Gradually, even Riezel was drawn by the wondrous breathing sound echoing in his ears, unconsciously mimicking it.

"Huuu... Haaa..."

Just as he had imitated Kyoujurou's breathing on the train, Riezel began to mimic the swordsman's breathing.

Regardless of frequency, number of times, amplitude, timing, quantity, or rhythm, Riezel unintentionally drew closer and closer to the swordsman.

*Ba-dump!* *Ba-dump!*

Eventually, the beating of his heart began to accelerate, while the flow of his blood also quickened.

His lungs expanded continuously, allowing Riezel to inhale larger and fiercer air.

Breathing in such large quantities of air, under normal circumstances, he might have worried about oxygen toxicity, but at this moment, he abandoned all thoughts and focused wholeheartedly on following the swordsman's breathing, immersing himself in the other's sword dance, almost unable to control himself.

In this state, Riezel failed to notice that as his breathing changed, the power surging from within him became stronger and more intense.

It was a power far beyond what he had experienced while imitating Kyoujurou's Flame Breathing.

A breathing style far more powerful than Flame Breathing, far surpassing the breathing style mastered by any Hashira of the Demon Slayer Corps, appeared before Riezel's eyes.

It seemed as if the swordsman intentionally wanted to pass on this breathing style to Riezel, moving over and over again, demonstrating tirelessly.

After hundreds of repetitions, the swordsman seemed to have endless energy, not tired at all, not fatigued in the slightest. His hand holding the sword didn't even tremble, and his posture remained flawless from start to finish.

However, there was only one problem.

"Sun Breathing consists of thirteen sword forms."

Every time he moved, the swordsman mechanically uttered that sentence, but from start to finish, only twelve sword forms were displayed in front of Riezel by the swordsman.

'Dance', 'Clear Blue Sky', 'Raging Sun', 'Fake Rainbow', 'Fire Wheel', 'Burning Bones, Summer Sun', 'Sunflower Thrust', 'Solar Heat Haze', 'Setting Sun Transformation', 'Beneficent Radiance', 'Sun Halo Dragon Head Dance', and 'Flame Dance'.

Clearly, the sword forms demonstrated by the swordsman remained only these twelve, never reaching the thirteenth sword form after countless repetitions. Yet, the swordsman repeated that sentence time and again, telling Riezel repeatedly that the breathing style named 'Sun Breathing' indeed consisted of thirteen sword forms.

Why?

Perhaps only Riezel, who was familiar with the original work would know why.

Just as Riezel's breathing synchronized completely with the swordsman's, and all the swordsman's sword forms were engraved into his mind, etched into the depths of his heart, the swordsman finally stopped moving.

"...I'll leave it to you."

At the very end, Riezel heard that barely audible murmur from the swordsman.

*Ding—ling—*

As the swordsman's earrings swayed, the sound of wind chimes resounded again.

Riezel felt as if the scene before him was fading away, his consciousness gradually drifting, slowly disappearing from this dream.