Moonlight bleached the Mass Grave Ridge white.
Xiaoyue crouched beside a corpse and peeled back the rotted cloth wrapped around it. The fabric had fused to the skin; she had to tear it free in two sharp pulls, and the sound it made was dry and thin, like paper splitting.
A middle-aged man. Dead roughly ten days, but showing no signs of decay — not from any preserving treatment, but because the water had been drawn entirely out of him, leaving nothing for bacteria to thrive on. The body had become a thing of dried leather: skin pressed flat against bone, muscles reduced to a thin, papery layer that felt like wood when she pressed it with her fingers.
She turned his arm over.
The cracks in his skin were deeper and denser than those she had seen on the living patients in the quarantine ward, the fissures packed with a grayish-white powder. She scraped a little free with her fingernail and held it to the light.
In the moonlight, the powder was fine as flour — but looking closely, she could make out the irregular, fractured structure of it. Not flaking skin. Not salt crystals. Not mineral residue.
She brought it to her nose.
A faint sweetness, with the edge of rot beneath it.
Her pupils narrowed slightly.
She set down the first corpse and moved to the next. An older woman, dead longer, dried further — the features of her face had fully collapsed, her eyes shriveled to two raisins. Xiaoyue pried open her mouth and examined the interior.
Gums withered. Tongue hard as cured leather. But at the base of the tongue, near the throat, she found something that should not have been there: a thin pale membrane, fine as cobweb silk, adhered to the mucosal lining.
Xiaoyue touched the tip of her little finger to it.
The membrane was brittle. It crumbled at the touch, breaking into still finer powder that scattered through the oral cavity. But in the instant of crumbling, she glimpsed the tissue beneath — not the gray-purple of ordinary postmortem decomposition, but a stark, unnatural white, as though something had drawn the blood out of it.
She examined three more bodies.
The same, every one: grayish-white powder in the skin fissures, the pale membrane coating the throat and oral cavity, the bloodless white tissue beneath. The degree varied, but the pattern was identical.
Last, she came to the most recently dead — a young woman whose face still faintly resembled a face, gone three or four days at most. She had not dried as severely as the others; her skin was desiccated but still held a little give.
Xiaoyue drew her small knife and opened a shallow cut along the inner forearm.
The blade entered wrong — too dry, like cutting a piece of wind-cured bamboo shoot, without the resilience of living flesh. The cut did not bleed. The exposed cross-section was grayish-white.
She parted the incision slightly and leaned close.
The subcutaneous tissue was equally desiccated, but between the shrunken muscle fibers she found what she had been looking for.
Thread-thin, nearly transparent filaments, wound around the muscle like miniature vines climbing a tree. They extended from just below the skin all the way down into the deeper tissue, too fine and too dense to distinguish with the naked eye from the outside.
They were dead and dry, but their form was preserved intact. Xiaoyue lifted one on the tip of her knife and held it to the moonlight.
Transparent. Hollow. One end swollen into a tiny spherical structure — a hatching sac. Or more precisely: the empty shell left after hatching.
She had her answer.
Gu.
Not an epidemic. Not a plague. Not any act of heaven.
This was gu poison, made by human hands.
The gu worm entered the body through the mouth and propagated membrane-like colonies along the mucosal lining of the throat and digestive tract, while extending filaments into the muscle tissue. The worm drew moisture and nutrients from its host, causing the host to desiccate from within. The grayish-white powder was the worm's metabolic waste, seeping out through the cracks in the drying skin. And the "cannot swallow a drop of water" symptom that had confounded everyone — it was not that the patients could not swallow. It was that the worm membrane in the throat blocked the digestive passage, so water swallowed immediately returned, expelled with each retch.
She had read about this in the archived texts of the Valley of Undying. Certain southern border tribes cultivated living gu using insects, worms, snakes, and scorpions, incubating them inside human bodies. But those gu were acute — fast to act, fast to kill. The variety afflicting Withered Leaf Town was different. Chronic. Long incubation. Slow onset. One to two months from infection to death. This kind of thing was not designed to kill one person. It was designed to kill an entire town.
Xiaoyue pocketed her knife and straightened.
The night wind moved across the Mass Grave Ridge, lifting the frayed edges of burial cloth, making the rags whisper among the bodies. The moonlight was cold and clear, throwing her shadow long across the scattered stones.
Her expression did not change.
She was surrounded by dozens of desiccated corpses. The air held the sweet, dry smell of slow rot. The wind came in off the dark like a blade. But her hands were steady, her breathing even, her heartbeat not noticeably faster than usual. One who has seen an entire household of bones does not startle at sights like this.
She was thinking through the treatment.
The gu worm was the carrier; the gray powder its waste; the membrane the root of the symptoms. Step one: kill the worm — suppress its activity with medicine, prevent further moisture absorption. Step two: dissolve the membrane — let the throat lining shed, restore the ability to swallow. Step three: expel the remnants — drive the dead worm bodies and metabolic waste out of the patient.
Three steps. Simple enough to state. But each step required the right medicine, and she had only read about this variety of gu — she had never treated it herself. Still, she remembered several formulas from the texts for suppressing gu activity. The key ingredients were mostly common warming and acrid herbs: Sichuan pepper, cinnamon bark, clove, dried ginger — available at any pharmacy. Warming and acrid substances accelerated the circulation of qi and blood; gu worms were yin-cold in nature and feared heat, acridity, and dryness.
She was still working through the proportions when the air behind her changed.
No sound. No smell. Only the most subtle shift in the movement of air — someone was approaching her. Someone who had deliberately suppressed their footsteps.
Xiaoyue did not turn around.
Her right hand moved quietly into her sleeve. Her fingertips found the cord of the petal pouch and pinched one petal free.
The presence drew closer. At roughly nine meters, it paused for a breath — then the airflow suddenly accelerated.
Here.
Her body moved before her mind could. She pivoted hard to the side and snapped her right hand outward; the petal left her fingers spinning, aimed directly at the face of whoever was behind her.
A brief metallic ring, like a muffled cough.
The petal had been deflected.
In the moonlight: a longsword extended across the space before her, still faintly trembling — that was what had batted away the petal. The one holding it was a young man, early twenties, a lean and upright figure in dark narrow-sleeved clothing. The scabbard at his hip was a deep blue-gray. A bronze medallion of the Zhige Platform hung at his waist.
His face was difficult to read in the moonlight, but Xiaoyue noticed his eyes — settled, composed, without killing intent, but watchful.
Zhige Platform.
Xiaoyue said nothing. Neither did he.
A second petal was already pinched between her fingers.
The young man's sword tip turned slightly and angled toward her left shoulder. Controlled speed, restrained force — a probe.
Xiaoyue stepped aside and flicked her wrist; the petal spun out not in a straight line but in a curving arc from the side, silent and invisible, aimed at the side of his neck.
He brought the sword around in a reverse grip and deflected it precisely. A soft *ting* — his hand paused for a fraction of a second. The petal was considerably harder than he had expected. Striking it was not like striking a flower petal. It was like striking a copper coin.
No time to reflect on it. The third petal was already in the air.
This one flew low, skimming the ground, then abruptly lifted at three paces out and drove at his wrist. Simultaneously Xiaoyue was moving — not retreating, but circling to his right, her footsteps silent as cotton.
He dropped his sword hand and caught the rising petal on the hilt-guard, then pivoted his feet to track her movement. His footwork was solid; his center of gravity low and stable; each step placed with precision — neither too close nor too far, maintaining exactly the right distance.
He had understood her. She was a ranged fighter; the optimal distance for the petal blades was beyond six meters. Close the distance, and she would have no room to work.
Xiaoyue raised her left hand. The fourth petal was not a spinning throw — she fired it straight, twice as fast as the others, driving for the center of his chest.
His eyes sharpened. The sword came up horizontal across his body and caught it. A sharp *ting*, and the petal sank half a cun into the blade.
He glanced down at it. The edge of the petal was darkened — treated with something.
He flicked it clear. The sword tip rose.
This time, no more probing. He drove off the ground and launched forward, the blade moving through the center line, aimed straight at Xiaoyue's right shoulder.
Fast.
At least twice the speed of his earlier passes.
Xiaoyue's pupils contracted slightly. Her body answered before her mind — she turned at the waist and slid left by half a step; the sword tip grazed the fabric of her sleeve, close enough that she felt the displaced air. The steel had come within two cun of her skin.
Too close.
His recovery was immediate: the missed thrust became a spinning horizontal cut. Xiaoyue dropped low; the blade cleared her head by three cun, pulling free several strands of her hair. With the momentum of the drop she fired a petal straight down — not upward, but along the ground, aimed at his ankle.
He jumped to avoid it. But Xiaoyue had waited for exactly that jump — a person in the air cannot change direction. The last petal left her hand in a spinning arc toward his torso.
He twisted in the air and brought the sword hilt down hard to knock the petal aside. The petal was deflected, but the torque of the mid-air twist threw his landing point half a step off; his foot came down on a loose stone, the stone shifted, and he staggered.
Just that one instant.
Xiaoyue was already inside his reach.
Her left hand had acquired a silver needle — not a petal, a true needle, short and fine, held between the first and second fingers. The tip aimed at his wrist.
At the same instant, his first move after regaining his footing was not a sword cut but a reversal: sword hilt forward, pressing against Xiaoyue's ribs.
Both of them stopped.
Needle at his wrist. Hilt at her ribs.
In the moonlight their shadows overlapped and fell tangled across the stones. They were close enough to read each other's eyes — Xiaoyue's were still as water; his held a flicker of surprise, and beneath it something more sustained, more deliberate.
Neither had spoken a word.
Three heartbeats of stillness.
Xiaoyue spoke first.
"I'm not a thief," she said. "I'm here to investigate the disease."
He did not sheathe the sword immediately. His gaze moved from her face to the body at her feet — the opened forearm, the pried-apart jaw, the bamboo skewers and the small knife scattered on the ground. Then back to her face.
The hilt withdrew from her ribs.
He stepped back one pace. The sword returned to its scabbard with a clean sound that rang out across the silent ridge.
"Pei Qingyan," he said. "Zhige Platform."
Xiaoyue pocketed the needle and stepped back as well.
"Lilu. Valley of Undying."
"Valley of Undying." He repeated it — no inflection of question, no trace of dismissal, only committing the three characters to memory. "I haven't heard of it."
"That's normal," Xiaoyue said.
She bent down and retrieved the bamboo skewers that had been knocked loose during the fight, then gathered the scattered petals — the salvageable ones went back into the pouch; the ruined ones she discarded. Unhurried, deliberate, as though nothing had just occurred.
Pei Qingyan watched her collect the petals. His gaze rested on those pale, paper-thin things.
"Petal blades," he said. "An unusual school."
"Your sword held back as well," Xiaoyue said, not looking up.
Pei Qingyan did not deny it. He had held back. But so had she — the petal trajectories had been devious and unpredictable, yet every single one had struck at his weapon or his limbs; not one had gone for a vital point. And the petals were treated with a numbing agent, not a poison. When he had deflected the first one, a trace had brushed his fingertip, leaving it numb but not painful. Someone who meant to kill did not use something like that.
"You passed over the roof of our post," Pei Qingyan said. "I followed you here."
Xiaoyue registered this. She had thought her steps were quiet enough — she had crossed that rooftop in under two breaths, in the middle of the night — and he had detected the movement from inside the building.
Exceptional hearing. Or, more precisely: an exceptional state of vigilance.
"I thought I was quiet enough," she said.
"You cracked a rafter."
Xiaoyue looked up at him.
His expression was composed, but she had the impression the corner of his mouth had done something it was not quite admitting to.
"Your rafters were rotten," she said.
Pei Qingyan did not take that up. He looked at the bodies arranged in their rough disorder around them, then at the opened corpse at Xiaoyue's feet, and his voice dropped. "What did you find?"
Xiaoyue tucked the last petal away and tied the cord, then straightened.
"Not a disease," she said.
Pei Qingyan waited.
"Gu."
The word was distinct in the night wind.
Pei Qingyan was silent for a beat.
Xiaoyue crouched down, lifted a filament on the tip of a bamboo skewer, and held it out on her palm for him to see.
"Thread-like worm bodies between the subcutaneous tissue and the muscle layer, with large quantities of post-hatching shells deeper in. The throat is obstructed by a worm membrane that blocks the digestive passage — that's why the patients cannot swallow water. They swallow it and the membrane pushes it back. The gray-white powder is crushed shell fragments and metabolic waste."
Pei Qingyan crouched across from her and looked closely at the transparent filament, then at the pallid tissue exposed in the incision. His brow pulled together.
"Chronic gu," Xiaoyue continued. "Long incubation period, slow onset. One to two months from infection to death. It doesn't spread between people — gu worms bond only with the first host they enter. That's why your Zhige Platform men stationed in the quarantine ward for weeks haven't caught it."
*Doesn't spread between people.* Pei Qingyan heard the implication in those three words — all the patients had been infected at the same time, through the same pathway. This was not the dispersal pattern of an epidemic.
It was the pattern of deliberate poisoning.
"Someone planted the gu," he said. Not a question.
Xiaoyue looked at him briefly. Fast. She had only said *gu*, and he had already arrived at *someone planted it*.
"The entire town infected simultaneously means the gu worms were transmitted through something everyone touched — the water supply, the food, or something else. You'd know that better than I would. You've been here longer."
Pei Qingyan rose.
"Can you treat it?"
"I can suppress it," Xiaoyue said. "But treatment alone isn't enough. The gu was placed by someone. If that source isn't found, cure them today and they'll be infected again tomorrow."
"The source," Pei Qingyan said, "I'll investigate."
Xiaoyue looked at him.
This man was direct. No superfluous words, no *I'll consider it* or *let me think it over*. She had said the source needed finding; he had taken it on without hesitation.
"Then we each handle our own part," Xiaoyue said.
"Each handles our own part." He nodded.
They stood for a moment in the center of the Mass Grave Ridge. The moon had moved well past its zenith; the wind had grown colder. The burial cloth on the bodies rustled in the gusts, almost as though whispering.
Xiaoyue turned and walked toward the town. A few paces on, his voice reached her from behind:
"Miss Lilu."
She stopped. Did not turn around.
"Sunrise tomorrow, come to the quarantine ward. Make a list of whatever medicines and supplies you need."
"Understood."
She kept walking.
Pei Qingyan stood at the high point of the ridge and watched her gray-green figure move away along the path. The wind caught the hem of her clothing and lifted it — a leaf taken up by the wind, silent and without weight.
He stood there a while.
Petal blades. Devious trajectories: arc, shot, ground-skimming rise — no two identical. And treated not with poison but a numbing agent. This young woman had examined corpses in the dark without flinching, and yet not one of her weapons had aimed for a vital.
Not that she couldn't use poison. She had chosen not to.
*Valley of Undying.* He hadn't heard of it. But the world was full of schools no one had heard of, and obscurity did not mean mediocrity.
His hand moved without thought to his waist — not toward the sword, but toward the small object tied beside the scabbard. His fingertips found the warm, smooth surface, paused, then let go.
He turned and walked back to the Zhige Platform post at a measured pace.
The first pale light was beginning at the horizon's edge. Withered Leaf Town was as silent as always — every door sealed, the air carrying its arid, sweetly rotten smell.
But something had changed.
At least now, there was someone who knew this disaster's true name.
Not a plague.
Gu.