Chapter 25

The noisy special training at the Butterfly Mansion Estate continued for several days under the Sapphire Star's "enthusiastic" guidance.

Though Zenitsu's screams still rang through the halls, his body could now instinctively dodge with remarkable efficiency when the Sapphire Star simulated a charging wyvern with Spirit Thrust, yelling, "Wyvern charge!!! Charge!! Gahahahahaha!!! Fighting feels awesome!!!"

Inosuke's boar instincts grew ever sharper as he dodged Barrel Bombs, making him as slippery as a Jyuratodus.

Tanjiro had ingrained his Breathing Style into his very bones. Even the rise and fall of his chest in sleep carried a steady sense of strength.

Aoi Kanzaki sighed over the new cracks in the training ground's floor, but even she had to admit that the three troublemakers were improving at an astonishing pace.

That afternoon, the Sapphire Star leaned against a veranda pillar, idly tossing a Whetstone as she pondered whether to trick Inosuke into a trap and use him as a moving target. Hikigusa appeared silently at the courtyard entrance, like a melting fragment of sunlight.

Her expression was graver than usual. She hurried over to the Sapphire Star. "Lady Sapphire Star."

"Oh? What's wrong, Miss Hikigusa?" The Sapphire Star casually tucked the Whetstone back into her waist pouch.

"Some loser demon causing trouble again? I'll knock its front teeth out and use them as dice!"

Hikigusa hastily shook her head. "We aren't certain yet whether this is simply the work of a demon. An extremely strange epidemic has broken out in a village to the west called Tsutaya Village."

She described it at a rapid pace:

"More than half the villagers have fallen ill. Persistent high fever, violent vomiting. But the strangest part is that they've become extremely sensitive to light! The moment they're exposed to sunlight during the day, their skin breaks out in red rashes. The itching is unbearable, and the pain is agonizing. Only after sunset, when night falls, do their symptoms ease a little and give them some relief."

The Sapphire Star rubbed her chin. "Sensitive to light? Why does that sound so much like..." She left the word "demons" unsaid.

"Yes, and nighttime is precisely the problem!" Hikigusa stressed.

"The villagers feel better at night, but something even more terrifying happens-people disappear under mysterious circumstances almost every night! Every Corps member we sent to investigate developed a high fever and vomiting shortly after entering the village. They couldn't investigate any further!"

"What about the Hashira?" the Sapphire Star asked.

"The Water Hashira is tracking a Lower Rank, there have been disturbances in the Wind Hashira's territory, and the Flame Hashira is far away in Kanto... The other Hashira also have their hands full," Hikigusa said anxiously.

"The Insect Hashira is already analyzing the disease and trying to develop medicine, but that takes time! Oyakata-sama fears the disappearances will only grow worse before the medicine is ready..."

"They're all busy enough to explode. No wonder a certain someone has such a rotten temper." The Sapphire Star rubbed her chin.

Hikigusa looked at her pleadingly. "Please go to Tsutaya Village and investigate! Your strength is extraordinary. Perhaps you can discover where this strange illness came from! But-!" She emphasized the word, her face full of worry.

"Please, you must, absolutely must, exercise the utmost caution! This epidemic is far too strange! Even swordsmen aren't immune. Powerful as you are, please take care of your health! Don't push yourself!"

"If you have time to investigate, shall I first take you to Lady Kocho to collect some protective medicine? The antidotes and preventative remedies prepared by the Insect Hashira..."

The Sapphire Star looked thoughtful. "No need for that."

Then she waved a hand, cutting off Hikigusa's suggestion, and produced a masterpiece crafted from Vaal Hazak materials-the Miasma Resistance Charm. Potent dragon-element energy and miasma-resistant runes flowed across its surface.

"See this? When it comes to all that nasty poison gas, germs, and miasma, I've got an old friend to rely on! Back in the Rotten Vale, I even took a bath in that disgrace of an Elder Dragon Vaal Hazak's poison pool with him. This little thing handles all sorts of stubborn ailments!"

The Sapphire Star chuckled, seemingly convinced that her protection was second to none.

"Besides, Hikigusa, you have no idea. One of my girlfriends-that idiot Blaze from Kamura Village I mentioned before-is the one who's riddled with afflictions! Berserk, Bloodlust, Strife, Dereliction. Once she gets enraged, red-and-black dragon energy even comes out of her mouth!"

Tanjiro, Zenitsu, and Inosuke, who were eavesdropping under the veranda, couldn't help pricking up their ears. Even Aoi and Kiyo, passing nearby with trays of medicine, stopped to listen to these tales of bizarre ailments from another world.

"But you know what's most badass about her? When she isn't patrolling her territory, she uses Wirebugs to fly up and intercept passing Rathalos. Then she sticks one in her mouth, takes a few sucks, and tops her health right up."

The eavesdroppers imagined the scene and stared, dumbfounded.

Far away in Kamura Village, Blaze was munching on rice dumplings when she began yawning repeatedly. "Achoo, achoo!!! That can't be right. I'm immune to every poison-can I still catch a cold...? Are Hinoa and Minoto missing me? Slurp... Achoo!"

The towel Zenitsu had been using to wipe his sweat dropped to the ground with a soft patter. His mouth hung wide enough to fit an egg. Tanjiro looked utterly shocked, as though he had heard some impossible fantasy. A clack came from inside Inosuke's Boar Headgear, probably because he had opened his jaw so far that it struck something. Aoi Kanzaki, Kiyo, and the others were completely petrified...

Noticing the boys eavesdropping, the Sapphire Star nodded in satisfaction. "So! Fever, vomiting, rashes? Small potatoes! Compared to my girlfriend, who goes around sucking on Rathalos while covered in red-and-black sinister energy, this little mess isn't going to stop me!"

She grabbed the Fatalis Demolisher leaning against the veranda pillar and swung it onto her shoulder with a boom, flashing a smile that gleamed coldly-purely because her teeth were so white.

"I never drag my feet on a job. Every second sooner I leave is one less second the villagers have to suffer. Let's go!"

"Wait! Miss Sapphire Star!" Tanjiro came to his senses and called out anxiously.

"Even someone as strong as you must be careful! When I was little, I saw a village struck by an epidemic. It can be even more frightening than a demon attack..."

"Waaah! Don't treat yourself like that bloodsucking girlfriend of yours! This is different!" Zenitsu wailed.

"Hmph! If you can't find the bastard who poisoned them, remember to leave someone alive for me!" Inosuke thumped his chest.

Aoi Kanzaki looked deeply worried. "Lady Sapphire Star, you... Are you really sure you won't reconsider taking some..."

"Relax, relax!" Without looking back, the Sapphire Star fired her Clutch Claw and flew over the wall. Her booming voice carried back to them. "Wait for my triumphant return! You three! No slacking!"

She left behind a sea of worried, stunned, and indescribably complicated looks.

Hikigusa followed helplessly beside the Sapphire Star. Looking at this otherworldly hunter in her inhuman armor, brimming with confidence, she felt a vein at her temple begin to throb.

Miasma-resistant equipment? A girlfriend who restores her health by sucking on Rathalos? This all sounds beyond common sense. Can we really rely on this woman to solve the problem...?

Before long, the ease vanished from the Sapphire Star's face. She stopped and spoke gravely to Hikigusa beside her.

"This is far enough. Don't follow me any farther." She rummaged in her waist pouch, pulled out a small block wrapped in oiled paper that gave off a rich medicinal scent, and pressed it into Hikigusa's hand.

"Take this. It's Herbal Medicine. It can cure poison and heal injuries. If anything happens, chew a couple of mouthfuls and swallow. No matter what happens, keeping yourself alive always comes first!"

Hikigusa wanted to say more, but when she saw the Sapphire Star's unwavering golden eyes, she merely tightened her grip on the warm block of medicine and nodded firmly. "Yes! Please be very careful, my lady!"

Without further delay, the Sapphire Star strode into Tsutaya Village alone.

The sight inside the village drew her brows into a tight frown.

It was afternoon, and the sunlight was fairly bright. It should have been a time for work and daily life, yet the entire village was deathly silent.

Every house had its doors and windows tightly shut. Light struggled through the cracks, barely illuminating the faces twisted in agony within.

The villagers lay collapsed on straw mats or in corners, their exposed skin densely covered in red, swollen, glistening blisters and bumps. Many scratched unconsciously, letting out stifled groans and anguished whimpers. The air reeked of sweat and sour vomit, mingled with an indescribable sense of agitation. To them, sunlight was no longer a source of life, but a source of torture.

It was as though an invisible hand had seized the village by the throat.

The moment the Sapphire Star stepped through the village entrance, a heavy mixture of sweat, sour, rotting vomit, and scorched herbs struck her, thick enough to feel suffocating.

Brows tightly knitted, the Sapphire Star deliberately avoided areas exposed to direct sunlight and walked steadily toward a house with its door half closed.

Inside the dim house, a withered old woman lay curled on a straw mat in the corner. Even the shabby, thin blanket covering her could not conceal the horrifying sight of her exposed skin-great patches of swollen, glistening blisters and bumps, packed as densely as the warts on a toad's back. Some had been scratched open and leaked yellow fluid, shining with a sickening oily sheen in the dim light.

The old woman scratched unconsciously, her throat rasping like a broken bellows. Every breath seemed to burn with pain.

"..." The Sapphire Star did not hesitate. Ignoring the sudden fear in the old woman's clouded eyes, she reached behind her waist and grabbed a large handful of herbal powder from a specially made leather pouch.

The powder flowed between her fingers like stardust, releasing a curious blend of herbal fragrances that instantly diluted the foul air in the room.

She selected a corner where the air moved more slowly, flicked her wrist, and scattered the powder with force!

Whoosh-!

A pale blue glow flickered through the dim room, and a miracle occurred:

Wherever the powder touched, the hideous red blisters on the old woman's skin rapidly subsided and flattened, visibly smoothing as though beneath an invisible hand! The tormenting itch that reached deep into her bones seemed to be quenched by cool spring water, and her scratched-open wounds healed before their eyes.

The old woman's taut body suddenly relaxed. The rasping in her throat became a long sigh of relief. Though she remained weak, the excruciating pain of feeling as though sunlight were burning her had clearly eased.

"Are... are you an... immortal...?" Tears welled in the old woman's clouded eyes as she struggled to rise.

"Just lie down, granny. No need to get up." The Sapphire Star spoke quietly. Without lingering, she turned toward the next house. She repeated the process in several open-doored homes where the patients were most severely ill.

Each time, stifled groans quieted, and a faint spark of hope rekindled in despairing eyes.

Her movements were brisk and efficient, without a single unnecessary word.

Soon, her actions and the powder's miraculous effects stirred the entire deathly silent village. The news spread like a feeble flame through the darkness of despair.

When the Sapphire Star stopped beneath the huge, leafy old pagoda tree at the village entrance, an elderly man with white hair and a white beard staggered toward her, supported by several villagers who could barely walk themselves. Traces of rashes and blisters still lingered on his face. He was Tsutaya Village's headman.

The headman's clouded eyes brimmed with incredulous gratitude and profound awe. He looked at the Sapphire Star's fearsome armor and enormous blade, plainly nothing of this mortal world, then felt the long-forgotten relief of his itching fading away. Bowing deeply, he spoke in a trembling voice. "Our savior... Are... are you an envoy sent by the gods? Or... one of those honored people from the Demon Slayer Corps?"

"You're giving me too much credit, sir. I was just lending a hand." The Sapphire Star waved dismissively.

"If possible, I also need plenty of clean, fresh water. The more, the better."

Her request carried the weight of a military order. The villagers now saw her as their sole hope of salvation, and they moved with unprecedented speed.

Before long, several buckets of clear water freshly drawn from the deep well, still giving off a cool mist, were carried beneath the tree.

Only then did the Sapphire Star retrieve a block of Herbal Medicine from deep inside her waist pouch and crush it. An intensely potent scent, mingling spice, bitterness, and overpowering medicinal strength, instantly spread through the air. Even the nearby villagers coughed and stepped back.

Ssshhh-!

The Sapphire Star sprinkled the crushed Herbal Medicine into the water. Like hot oil meeting water, it instantly stirred up a string of tiny bubbles with a faint sizzling sound.

The water churned. An even stronger medicinal fragrance rose, no longer pungent but carrying a strange, sweet aftertaste. It quickly replaced the earlier overpowering smell and tinted the entire bucket a very pale blue.

"Please drink one small spoonful each. Those who have the strength, please help give it to anyone still suffering from fever and vomiting." The Sapphire Star pointed at the bucket of diluted medicine, her voice clear and firm.

"Remember! No more than one small spoonful per person! This stuff is powerful. Too much, and your bodies won't be able to handle it. You might get nosebleeds." She knew exactly what the life energy contained in this top-quality medicine from the New World meant for the villagers' frail bodies. Dilution and strict dosage control were essential.

The villagers obeyed, carefully scooping up the medicine with wooden spoons.

The medicine tasted bitter, but soon turned into a peculiar warm current that slipped into their bellies. For those who drank it, the violent urge to vomit was forcibly suppressed, and their churning stomachs strangely settled. The alternating chills and fever that seemed entwined in their very marrow, leaving them dazed and longing for death, also seemed to ease beneath that gentle but steady warmth. At last, a little color returned to their sallow faces, and their flagging spirits visibly revived.

"An immortal!" "Thank you for saving our lives!" "You've given all of Tsutaya Village a second life!" Gratitude for surviving disaster surged like a tide. In an instant, the villagers beneath the tree dropped to their knees, sobbing too hard to speak.

"All right, all right. Get up, everyone. Get up. You don't need to kneel to me... Oh, sir, please...!" The Sapphire Star awkwardly helped the kneeling villagers up one by one, then finally turned to the headman.

"You're the village headman, right? Could you please tell me how this deadly epidemic started? Who fell ill first? Before anyone got sick, did anything strange appear in the village or the nearby mountain forests? Or did any unfamiliar faces or odd things come into the village?"

The gratitude on the headman's face instantly froze, replaced by bone-deep fear and hesitation. His cracked lips trembled. The villagers around him lowered their heads, and a silence more unsettling than the epidemic itself spread through the air...

"My lady... You're asking where it began... This... this matter..." He swallowed with difficulty, his voice hoarse, and finally spoke.

"Our village... Since ancient times, we've worshipped the deity in the Rotten Wood Shrine on the mountain behind us... There... we worship Lord Kodama, who protects the forest and our village..."

The headman's voice held a trace of lingering reverence and regret so thick it could not be dispelled.

"The shrine... is very old indeed. Wind and rain have rotted the wood, and the statue... is old too... But we've never dared neglect our offerings. At festivals and holidays, the villagers always go to clean it, offer tribute, and pray for peace and a good harvest!"

His account grew painfully difficult.

"But! About... half a month before the epidemic broke out, the woodcutter Genjiro went there to worship. Not long after he came back... he started feeling unwell. A headache, a little weakness... His wife mentioned it to me. She said he looked a bit pale and listless when he came home that day. But none of us thought much of it. We assumed he was tired from chopping wood and had caught a chill from the mountain wind..."

The headman's fists clenched unconsciously, his nails nearly digging into his palms.

"...Two or three days passed, and instead of getting better, Genjiro developed a fever and started vomiting terribly!"

"Then two more... two villagers who had gone to worship after him... developed similar symptoms! People... people began to think something was wrong... Some whispered in private... wondering whether the deity..."

The headman suddenly raised his voice, as though trying to drive away that dreadful thought-or, more likely, shouting for his own benefit.

"I scolded them right away! How could our revered deity send down a disaster? Tsutaya Village has worshipped him for generations without ever letting the incense go out. Surely... surely they'd accidentally touched something unclean in the mountains! Or eaten some wild food that made them sick!"

The headman breathed heavily, beads of sweat forming on his forehead.

"I... I forbade them from discussing the shrine! The deity would punish us! I told everyone to clean the shrine thoroughly and make offerings with twice the devotion, hoping to soothe any displeasure he might have... But... but..."

His voice suddenly fell.

"But it didn't help! Among the people who went to clean the shrine... more collapsed! Their symptoms were exactly the same! And... and the first people to fall ill, like Genjiro... their illness started becoming terrifying! The moment they saw sunlight, their rashes felt as though they were burning, and the itching was unbearable. Their fevers made them delirious... At night... they felt a little better at night, but... but..."

His lips shook violently, and he could barely force out another word. Fear and guilt overwhelmed him. The faces of the villagers who knew the truth were filled with the same terror.

The Sapphire Star listened quietly until he finished, then gently patted his shoulders again as they shook with emotion. "You and the villagers have suffered terribly, sir. Thank you for telling me all this. It's very important."

She straightened and looked toward the densely forested mountain behind the village, which seemed especially gloomy even in the sunlight. The Rotten Wood Shrine lay hidden within it.

"I understand the situation," she said simply. Then she took another block of Herbal Medicine from her waist pouch and solemnly placed it in the headman's bony hands.

"Keep this safe, sir," the Sapphire Star instructed.

"If any more villagers fall ill, take a tiny piece, only as thin as a strand of hair." She indicated an exceedingly small amount with her fingers.

"Dissolve it in a large bowl of clean, warm water, stir it thoroughly, and give it to the patient to drink."

With trembling hands, the headman accepted the precious medicine as though clutching a lifeline. His clouded eyes filled with gratitude and the weight of the responsibility entrusted to him. "I... I understand, my lady! Thank you for giving us this medicine! We... we cannot thank you enough!"

The Sapphire Star nodded and took one last look at the villagers around her, their eyes filled with hope, fear, and exhaustion. Her voice rang clear and strong.

"Stay somewhere cool and shaded, rest, look after the sick, and drink plenty of clean water. I'll go investigate the shrine. Until I return, keep yourselves safe!"

With that, the Sapphire Star stepped without hesitation onto the winding trail behind the village, leading deep into the gloomy mountain beneath trees so dense that sunlight could barely penetrate. Her figure quickly vanished into the shaded forest in the direction of the Rotten Wood Shrine, leaving the villagers with their silent prayers and heavy hopes.