The Sapphire Star lay sprawled on the tatami, the cool straw mat pressed against the back of her neck. She was dead tired, yet her mind felt like a restless Palico frantically clawing at a door.
"Breathing Styles... Breathing Styles..."
She abruptly sat up.
"No! The more I think, the hungrier I get!"
Night had deepened, and headquarters was silent. The Sapphire Star slipped into the kitchen without a sound.
Before long, a small pile of empty bowls and plates had accumulated in the clearing, enough to rival a small herbivorous wyvern's meal. She had wolfed down a midnight snack equal to thirty ordinary Corps members' portions-
Rubbing her warm stomach, she felt that intense craving settle into quieter contemplation.
She returned to her quarters and lay down again, hugging the icy Fatalis scabbard to her chest. Its chill finally cooled her overheated mind.
"Well, nothing else to do now. Sleep first, go at dawn. Once I've slept enough, I'll be a little more respectful, too... That's the plan!"
Early the next morning, the first faint light appeared.
The Sapphire Star woke refreshed, feeling better than ever. The enormous midnight meal seemed to have transformed into abundant energy.
She slid open the door. Sure enough, Hikigusa stood silently beneath the veranda like a shadow.
"Miss Hikigusa, is the Master available right now? I'd like to ask him a few questions about the fundamentals of training."
Hikigusa bowed slightly.
"The Master has finished his morning sutra recitation and is having breakfast. Please follow me."
They passed through the peaceful morning corridors, the air filled with the fresh scent of dew and wisteria.
Hikigusa stopped before a sliding door painted with wisteria blossoms and knocked softly.
Kagaya Ubuyashiki's gentle voice came from within.
"Come in."
The Sapphire Star pushed open the door. Kagaya Ubuyashiki sat upright before a low table, his complexion much better than yesterday.
A gentle smile appeared on his face when he saw her.
"Good morning, Sapphire Star. Please sit. How may I help you?"
The Sapphire Star sat cross-legged, gathered her thoughts, and looked candidly at Ubuyashiki.
"Sorry to disturb you, Master. Yesterday, near the training grounds, I saw the Corps members practicing a special breathing technique."
"It seemed particularly helpful for improving basic physical abilities-stamina, explosive power, sustained combat capability. I was wondering... do you have any texts or explanations of its fundamental training principles that I could consult? I'm simply interested in exploring the true nature of power."
Kagaya Ubuyashiki listened quietly, a flicker of understanding crossing those eyes that seemed capable of seeing into people's hearts.
He was silent for a moment, his gaze resting on the Sapphire Star's inhuman armor and enormous blade.
"Breathing Styles..." Ubuyashiki's voice carried a distant weight.
"They are the foundation that allows our Demon Slayer Corps swordsmen to transcend ordinary human limits. They are more than mere techniques. They are a resonance between heart, body, skill, and will."
He looked at the Sapphire Star gently.
"The power you have displayed already exceeds anything Breathing Styles can attain. With your level of mastery and insight, restricting yourself to learning the 'forms' of others might instead constrain your own vast power."
The Sapphire Star listened attentively without interrupting.
"However..."
Ubuyashiki shifted his approach.
"Perhaps the essence of power has something in common across its different manifestations. If you are interested in the path of 'breathing' itself and wish to explore its underlying principles, I do have something that may offer you inspiration."
He turned toward Lady Amane, who stood beside him, and gave a slight nod.
Lady Amane understood. She rose and went deeper into the inner room, carefully bringing out a long object wrapped in dark purple silk. She solemnly placed it on the small table before the Sapphire Star.
"This is something passed down through generations of the Demon Slayer Corps."
"It is not a manual illustrating the sword forms of any particular Breathing Style, but a collection of notes recording our predecessors' insights and deductions concerning the essential power of 'breathing.' They describe the circulation of 'energy,' the focusing of the 'heart,' and the various possibilities of uniting 'intent' and 'strength.' It is more like a key, one that opens the door to a deeper understanding of your own power."
He looked at the Sapphire Star with hope in his eyes.
"With your insight and strength, rather than learning fixed 'forms' from others, you would be better served by contemplating the source of this 'path' yourself. Perhaps you can discover a way uniquely your own to unite your immense frost power more perfectly with the source of your life."
Looking at the securely wrapped books before her, the Sapphire Star solemnly extended her scale-armored hands and carefully picked them up.
"Understood! Thank you for trusting me, Master. I'll... study them carefully."
Once she left the room, the Sapphire Star could no longer contain her grin. Cackling, she scurried happily back to her room.
Back in the guest room, the Sapphire Star slowly untied the books' silk ribbon and unfolded the soft, dark purple cloth layer by layer.
The thick, yellowed notebooks emerged, bearing the marks of age. She carefully opened the first volume. The vigorous script at the beginning immediately caught her attention.
"Breathing is the root of life, the bridge of strength. Each inhalation draws in the energy of heaven and earth, filling every bone; each exhalation expels the body's impurities, focusing the spirit and gathering strength. It is not confined to mouth and nose, but encompasses the opening and closing of every pore, drawing energy into the smallest reaches and guiding strength like the tide..."
"It's all this fancy classical language... I hate reading classical texts..." The Sapphire Star could only force herself to read on, word by word.
The circulation of "energy," the effects of different breathing rhythms on explosive power and endurance, the guidance of the meridians...
Exhale-in-
She lost track of time reading, not because the books had engrossed her, but because understanding the archaic writing took so much effort. She had nearly scratched a bald patch into the top of her head.
At the end of the final notebook, several lines of wild, unrestrained handwriting and a crude circulation diagram made her brow furrow.
"The sun... the source of all paths... kindle the heart's fire, draw upon the blazing sun... energy circulates through the full circuit, unhindered and unimpeded... between the birth and death of strength..."
"Ugh..." The Sapphire Star rubbed her head, thoroughly bewildered.
Forget it. Reading all this isn't as good as getting straight to practice... I'm so smart, why should I follow a book?
Especially that last bit about the sun and the source of all paths. Sounds like some ancient guy talking out of his ass. I'm not bothering with that.
She closed the notebooks and carefully wrapped them again.
She needed more space, a more untamed environment in which to experiment and grow accustomed to this unfamiliar power.
Night deepened, and the first stars appeared.
Without alerting anyone, the Sapphire Star changed into a relatively lightweight hunter's underlayer.
Her transformed scabbard shimmered with a faint blue glow in the darkness. Like a ghost melding into the night, she left headquarters without a sound and raced toward the remote mountains, far from any settlements.
Under the moonlight, she moved as swiftly as the wind along the rugged mountain paths. The breathing rhythm described in the books gave her long, steady breaths and barely drained her stamina. It felt even more badass than Dash Juice.
Soon, she found an ideal spot-
A relatively level clearing in a moonlit valley, with a murmuring stream beside it and jagged rocks and dense ancient trees all around.
"Heh heh heh~ Not bad, not bad. This is the place."
Exhale-in-
Deep, drawn-out breaths with a distinctive rhythm sounded through the silent valley.
With each breath, Fatalis's dragon element and Velkhana's chill surged and swirled around her like awakening Elder Dragons!
The grass beneath her feet instantly acquired a thick coat of white frost, which rapidly spread outward!
She began to move.
There were no fixed techniques, only the most fundamental punches, kicks, evasions, and lunges!
The movements looked simple, yet held battle instincts honed through countless trials, now incorporating the entirely new flow of power brought by the Breathing Style!
She moved faster and faster, her strength becoming increasingly concentrated. The dragon and ice elements surrounding her surged and roared like living creatures, turning the entire clearing into a domain of frost! The stream froze solid, icicles covered the ancient trees, and hard ice encased the rocks!
The Sapphire Star abruptly stopped moving. The surging ice-blue chill around her slowly receded and settled.
She stood in the center of a glittering world of ice crystals, her golden eyes startlingly bright beneath the moonlight, feeling the unprecedented cold power within her obey her every command, alongside an inexhaustible well of stamina.
"Looks like I've got a little talent after all. I just keep impressing myself more and more..."
Satisfied, the Sapphire Star exhaled a breath of icy mist and was about to bend down to pull the Fatalis Demolisher from the rock beside the stream.
At the very instant her center of gravity shifted-
Whoosh!
A shrill sound tore through the valley's silence! A vacuum wind blade formed from rapidly compressed air, sharp enough to slice through rock!
With extreme speed, it shot down from the top of a towering rock wall in the shadows to her side, aimed straight at the center of her back!
Her battle-honed hunter's instincts sounded an explosive warning in her mind!
"Holy shit, an ambush! Who's jealous of my beauty?!"
The instant she evaded with a Foresight Slash-
Clang-!!!
The Sapphire Star slid sideways so quickly that she left a blurred, ice-blue afterimage behind.
The invisible vacuum wind blade, powerful enough to bisect a vicious demon, skimmed past her armored ribs by the narrowest margin!
The wind blade was not strong enough to damage equipment made from Fatalis, but the ambush still startled the Sapphire Star.
The violent air currents trailing the blade struck the field of icy energy around her with a piercing scrape. Finally, the blade slammed into a massive boulder behind her, covered in a thick shell of ice!
Boom!!
The Sapphire Star's figure solidified several meters away. She landed steadily with one knee slightly bent and instantly pinpointed the source of the attack.
Atop that towering rock wall, the moonlight outlined a wild, unrestrained figure.
His gray-and-white spiky hair bristled defiantly. His scar-crossed face looked even fiercer beneath the moonlight, and knotted muscles showed beneath his open Demon Slayer Corps uniform.
His eyes burned with intense fighting spirit and undisguised... brutality!
Sanemi Shinazugawa!
"Help, I'm being assaulted!!! Some pervert's ambushing me!"
Like a bird of prey locking onto its target, he stamped both feet against the edge of the rock wall!
Boom-
The rock beneath his feet shattered and fell!
The Wind Hashira himself used that explosive recoil to dive straight down at a speed even more terrifying than the wind blade's!
"You're the pervert! The name's Sanemi Shinazugawa!"
Wind Breathing, Third Form: Clear Sky, Wind Tree!
Countless spiraling wind blades grew like rampant vines, layering over one another and sealing off every avenue of escape!
The Sapphire Star instantly realized who he was-
That white-haired powder keg from the meeting!
"I knew this porcupine had it in for me!"
There was no time to reason with him!
Crack-crack-crack! The ice beneath her feet split into a spiderweb of fractures as she launched herself into the air!
Rather than retreating, she advanced.
Deep, icy breaths swelled within her chest, and her newly learned breathing rhythm poured strength into her legs.
At the same time, she crossed her arms before herself, and the scales on her bracers instantly thickened.
Without dodging or retreating, she charged head-on into the wind blades coming to shred her!
Her arms swung like two crossed, heavy hammers of ice!
Bang! Bang! Bang! Bang!
The tightly packed, teeth-grating blasts sounded like hail hammering a steel plate!
Countless sharp wind blades sliced against ice armor infused with the utmost cold, sending sparks and shattered ice crystals flying!
"Hah!"
The instant she broke through the vortex of wind blades, the Sapphire Star cried out sharply. Her right fist shot forth like an ice cannonball, wrapped in compressed, condensed cold. It tore through the remaining wind resistance and hurtled toward the Wind Hashira Sanemi's face with enough force to freeze the space around it!
A flicker of surprise crossed Sanemi's eyes! Not at her strength, but at the fact that she had broken through his attack in such a manner!
But his reaction was lightning-fast!
Wind Breathing-its essence lay in "movement"!
He leaned back to his absolute limit!
The Sapphire Star's cold-packed fist swept past the tip of his nose with a bone-piercing frozen gust. The intense chill instantly stung and numbed the skin of his cheeks!
At the same time, the fingers of his empty left hand curled like claws. Carrying concentrated vacuum wind pressure, he viciously struck at the opening beneath the Sapphire Star's ribs! Wind Breathing, Fourth Form!
The Sapphire Star dropped her left arm to block!
Clang!!!
Another deafening clash of metal rang out!
Using the impact and the momentum of her missed punch, the Sapphire Star twisted through her waist, spinning rapidly in midair like a top!
The tip of her left foot, carrying the force of that rotation, tore through the air with a sharp shriek and lashed viciously toward Sanemi's temple!
It was a standard hunter's kick, but infused with the rhythm of breathing, its power multiplied!
Fighting spirit blazed in Sanemi's eyes! So fast! So heavy! Those aren't hand-to-hand techniques a human could possibly pull off!
He jerked his head aside. Simultaneously, the Nichirin Blade in his right hand darted up from below like a striking snake, thrusting in a straight line with a concentrated wind blade toward the shoulder blade the Sapphire Star had exposed with her spinning kick!
Wind Breathing, First Form!
Attack! Defend! Attack again!
The two collided violently like a pair of raging storms!
In the space of a few breaths, they had exchanged dozens of blows!
The Sapphire Star flexed her arms, slightly numb from the impacts, and looked at the Wind Hashira opposite her, his fighting spirit soaring.
He's a Hashira of the Demon Slayer Corps, so I definitely can't get serious. But just defending like this isn't going to solve anything, either.
"Enemies who attack without saying a word are such a pain..."
He's going for the kill. I should hit back a little, too.
Sanemi also steadied himself, his chest heaving. The edge of his haori at the shoulder had acquired a layer of white frost from the cold escaping during the Sapphire Star's counterattacks.
He stared at the strange ice armor covering her entire body and that vicious-looking giant blade. Bloodlust and curiosity mingled wildly in his eyes as he finally spoke.
"You... really aren't normal! Tell me-"
He abruptly raised his Nichirin Blade, pointing its tip straight at the Sapphire Star.
"That power of yours-are you human or a demon?! You appeared before Oyakata-sama without a sound! If you can't give me an explanation I can believe! Wind Breathing..."
Sanemi lowered his body slightly. Violent wind pressure gathered around him like a vortex, and a chilling, high-pitched howl filled the air!
"...What a damn hothead!" The Sapphire Star's golden pupils contracted slightly.
The green winds coiling around Sanemi Shinazugawa's Nichirin Blade had condensed into a tangible, enormous vortex of wind blades, extending and retracting like fangs-Wind Breathing, Seventh Form: Strong Wind: Tengu Wind!
Faced with this terrifying killing move, powerful enough to grind mountain rock into dust-
Ding-!!
A chime, eerily clear, rang out the instant the storm of wind blades reached her!
The Fatalis Demolisher's massive gathering strike at red sharpness!
Under Sanemi the Wind Hashira's horrified gaze, the Sapphire Star did not retreat. Instead, she charged straight into that devastating vortex of wind blades in a way he could not comprehend, a way that defied the laws of physics!
Her movements were stripped down to the absolute essentials!
Each time a wind blade was about to touch her body-
Clink! Clink! Clink! Clink! Clink!
That enormous vortex of wind blades, seemingly fierce enough to pulverize mountains, broke apart inch by inch beneath the Sapphire Star's eerily precise attacks, collapsing like a punctured bubble!
The raging wind pressure froze, tore apart, and scattered into countless chaotic currents!
"What...?!"
Sanemi's pupils contracted sharply! He had never seen such a bizarre way of fighting!
This went beyond anything he understood as "martial skill"!
Every one of those chimes seemed to strike his nerves! What was that?! Something supernatural?!
The instant the final wind blade at the core was pierced!
The Sapphire Star emerged like a phantom from the center of the collapsing storm! The Fatalis Demolisher in her hands traced a powerful arc, and the ice-blue, dragon-shaped energy coiling around its blade instantly contracted, gathering at its tip!
Spirit Thrust!
Hiss-!!!
Every hair on Sanemi's body stood on end. He roared, pushing his Wind Breathing to its limit!
His body jerked backward as though a powerful gust had forcibly dragged him away, narrowly escaping!
Riiip-!
The blade's gleam skimmed his chest! His open uniform tore apart in an instant! An ultimate cold that penetrated his marrow, as though it would freeze even his soul, invaded his body!
Sanemi staggered as he landed. Looking down at the frozen wound across his chest, black vapor rising from it, he panted heavily, his eyes filled with incredulous horror!
What kind of blade was that?! What kind of power?! Freezing flesh and extinguishing life?! This was not a power humans could wield!
The Sapphire Star slowly sheathed her sword, its blade giving a low hum.
"I told you, I'm a hunter who somehow ended up on Mount Fujikasane and was taken in by Oyakata-sama. Why won't you believe me?" She paused.
"If I were a demon, or had even the slightest ill will toward the Demon Slayer Corps or the Master... I could've cut everyone and half the headquarters to pieces with one swing while they slept in the middle of the night! Can you please think for a second?!" The Sapphire Star flipped Sanemi the middle finger.
Seeing the suspicion and savagery still churning in Sanemi's eyes, she shook her head slightly, a hint of weariness creeping into her voice:
"I never thought about all those schemes and conspiracies. I just saw monsters, and I..."
She patted the enormous Fatalis blade.
"Couldn't stand by and do nothing. It's that simple!"
Her gaze passed over Sanemi toward the indistinct outline of the headquarters, and her voice lowered:
"If my presence really makes you... or rather, the Demon Slayer Corps uneasy..." She took a deep breath.
"Then I'll leave the headquarters and save you the trouble! I'm not interested in proving over and over that I wouldn't hurt a fly!"
"Leave?" Sanemi's voice was hoarse and warped with pain and anger as he stepped forward.
"What do you think the Demon Slayer Corps Headquarters is? Somewhere you can come and go as you please? Your story is full of holes! Do you think you're fooling a three-year-old?!"
The bloodshot veins in his eyes grew denser:
"The Master is compassionate, and you've deceived him! But you won't deceive me! Letting a dangerous freak like you leave, someone who even knows the secrets of our Breathing Styles, would be the greatest threat to the Demon Slayer Corps and everyone else! Today, either you tell me everything, or..."
He tightened his grip on his Nichirin Blade again. The blade hummed, and green winds rose once more, though noticeably weaker this time.
"You stay here for good!"
The Sapphire Star slowly turned around. Cold surged out again, gathering around her in roiling ice-blue mist!
"Oh, come on, you spiky-haired idiot! I told you I've got nothing to confess!"
With a slight movement of her wrist, the heavy Fatalis blade gave a low hum, its tip locking onto Sanemi Shinazugawa.
Another Spirit Thrust!
Boom!!!
The ice-blue meteor slammed into the green storm!
Sanemi's raging vortex of wind blades was forcibly torn open by that intensely concentrated thrust, leaving an enormous gap!
Golden light flashed in the Sapphire Star's eyes! The strength in her core erupted like a volcano! Using the impact and brief airtime gained from breaking through the wind pressure with Spirit Thrust, she drove both feet against the empty air.
Helm Breaker!
Defying physical limits, her body forced its way upward against the raging wind pressure and shot into the sky!
She rose over ten meters in an instant, leaving the Wind Hashira and his not-yet-dispersed storm of wind blades far below!
"Haaah-!!!"
A clear, fierce shout split the night sky!
The Sapphire Star plunged like a meteor! The Fatalis blade in her hands bore the force to destroy heaven and earth as she brought it crashing down at the Wind Hashira, who had only just looked up, astonishment still lingering in his eyes!
Helm Breaker Slash!
Before the blade even reached him, its terrifying pressure cracked the ground beneath Sanemi's feet! Roaring, he drove his Wind Breathing to its limit and braced his Nichirin Blade horizontally, ready to withstand that devastating blow from above!
But!
In the instant before her blade touched the Nichirin Blade Sanemi had raised to block!
Boom! Boom! Boom! Boom! Boom! Boom!...
Like a barrage of heavy artillery pounding the earth!
Dozens of deep-black blade flashes, wreathed in ice-blue auroras, slammed into the hard frozen soil and rock within several meters!
Sanemi stood frozen in place, still holding his blocking stance.
The world-shattering collision he had expected never came. Only violent shock waves mixed with shattered stone battered his body.
Beneath his feet lay an enormous ring-shaped crater several feet deep, riddled with terrifying, crisscrossing sword marks! He himself stood at the very center of that ring of death, completely untouched.
The dust slowly cleared, revealing the Sapphire Star where she had landed.
She panted lightly, her golden eyes looking through the drifting ice dust at the figure standing rigid as a stone statue in the crater's center.
"..."
Sanemi Shinazugawa slowly lowered his blocking Nichirin Blade. He looked down at the horrific crater beneath his feet, as though a meteor shower had struck it, then raised his head toward the foreign warrior standing at its edge with her sword sheathed.
The savagery and killing intent on his face froze, replaced by an incredulous sense of absurdity.
That attack... that slash from the sky, carrying such destruction... if it had landed on me... Sanemi had no doubt he would have been cut in two instantly!
But she... missed?! No! She hadn't missed! Those dozens of blade flashes had surrounded him precisely, yet not one had landed on him! That couldn't have been a mistake! She had... done it deliberately?!
"You...!"
Sanemi's voice was dry and hoarse, filled with incomprehension and the humiliation of being looked down upon.
"Why?! Are you toying with me?! Or..."
His voice suddenly rose, furious at being made a fool of.
"You don't dare kill me?! Afraid you'll expose yourself as a demon?!"
The Sapphire Star slowly straightened, shook out her wrist, and slid the Fatalis blade into its sheath with a clang.
Looking at the Wind Hashira in the crater, bristling like an angry hedgehog, a trace of helplessness crossed her face, along with a hint of... frustration that only she understood:
"For fuck's sake, how is TGY still screwing me over here?! My Helm Breaker whiffed again?! This stupid sword always missed back home, and it's still doing it here?! Is there something wrong with the hit detection on humanoids? I'll have to try it on a bigger monster next time..."
She took a deep breath, suppressed her internal complaints, and looked up at Sanemi:
"Toying with you? Do you think I've got nothing better to do?"
She pointed at herself.
"I'm your fucking mother! The Sapphire Star! The Sapphire Star who lights the way in the New World! I've cut down Shara Ishvalda! Slaughtered Safi'jiiva! Danced cheek to cheek with Alatreon! I even soloed Fatalis in seven minutes and twenty-nine seconds! I'm a goddamn hunter through and through! A perfectly respectable citizen!"
Her voice echoed through the valley, carrying an unquestionable ferocity and... a hint of hurt at being falsely accused...
"As for why I didn't cut you down?" She pursed her lips and pointed at the terrifying sword marks in the crater, saying guiltily:
"If I wanted you dead, that slash would've landed on you! If I were a demon, or meant the Demon Slayer Corps harm, would the Master still be alive? Would the headquarters still be intact? Would I have to be out of my mind to come train in these godforsaken mountains in the middle of the night just to wait for you to show up and cut me down?"
Seeing the lingering suspicion and conflict in Sanemi's eyes, she finally lost all patience and scratched irritably at her hair:
"Fine, fine! Believe whatever you want! I'll leave! I'll just leave, all right?!"
She turned and walked away from the headquarters without looking back.
"This shitty place... it's even more of a fucking pain than the Guiding Lands! Can't cut down demons, can't cut down people either...
"Lone Bird! Just you wait! Wait until I find my way back! And Blaze! You're in for it too when I get back to the Old World!"
Before you continue