Before Kiyohiko could respond, a cold flash of steel cut through the darkness.
Shinobu drew a small surgical knife used for preparing medicine from the sash at her waist.
Her movements were smooth and unhesitating as she dragged the blade across her pale left palm.
Bright-red blood immediately welled from the cut and trickled down her slender fingers, falling onto the wooden floor of the dojo with soft, rhythmic drops.
Drip.
Drip.
“There.
Now we have an injured patient.”
Shinobu held her bleeding hand out toward Kiyohiko as casually as though she were showing him a toy she had only just purchased.
Her tone was so light that one might have thought she had sliced through something other than her own flesh.
“Come along, Kiyohiko-kun.
Show me how a demon ‘saves’ someone.”
Kiyohiko froze.
The complaints he had already prepared became lodged in his throat as an unprecedented shock struck him directly through the skull.
It was the smell of blood.
To a demon, human blood usually represented sweetness, temptation, and an appetite nearly impossible to suppress.
The blood of a Hashira, whose body had been tempered through countless battles, should have been even more irresistible.
Yet what entered Kiyohiko’s nose was nothing resembling the aroma of a delicacy.
It was a stench.
The suffocating, overwhelmingly concentrated stench of wisteria.
This was not the faint fragrance of a sachet clinging to her clothes, nor was it anything that could be mistaken for perfume.
The smell was rising directly from Shinobu’s blood, as though every drop and every cell in her body had been thoroughly saturated with highly concentrated wisteria poison.
It was like taking the finest steak in the world and injecting it with an entire syringe of concentrated sulfuric acid.
“…”
The playful expression vanished completely from Kiyohiko’s face.
His features stiffened for an instant before his brows drew tightly together.
The evasiveness and humor within his eyes disappeared, replaced by a gravity—and even horror—that Shinobu had never seen from him before.
Rather than immediately activating his Blood Demon Art, Kiyohiko instinctively stepped forward.
Completely ignoring the wooden sword still held in Shinobu’s other hand, he seized her injured wrist.
“Hmm?”
Shinobu blinked.
She had expected the scent of blood to make him bare his fangs in hunger, or perhaps the wisteria poison would force him to recoil in disgust.
He did neither.
Kiyohiko stared fixedly at the blood spilling from her palm, his nose twitching as the nauseating scent confirmed his suspicions.
“What have you done to yourself?”
His voice had dropped into a low register.
Every trace of his usual frivolous tone was gone, replaced by a question barely containing his anger.
“I’m testing your ability.”
Shinobu tilted her head.
Although his reaction had surprised her, the same flawless smile remained upon her face.
“What’s wrong?
Is my blood so ‘fragrant’ that you cannot help but—”
“Stop joking!”
Kiyohiko cut her off so sharply that his voice echoed through the empty dojo.
He raised his head and stared directly into Shinobu’s eyes, his demonic gaze so piercing that it seemed capable of cutting straight through her carefully maintained mask.
“This concentration couldn’t possibly come from an ordinary diet.
Even if you ate wisteria flowers with every meal, your blood still wouldn’t become this poisonous!”
He pointed toward the wound that continued bleeding across her palm, his finger trembling slightly.
“You smell as though you’ve stuffed every drop of poison on Mt.
Fujikasane into your body.”
“This isn’t self-defense.
You’re turning yourself into a walking container of poison!”
Shinobu’s smile froze.
For a single moment, she felt as though she had been left standing naked within a frozen wasteland.
The deepest and most unhinged secret hidden inside her—something even Kanao did not fully understand—had been dragged into the open by a demon she had known for only a few days, all because of his sense of smell.
“This is enough poison to kill someone…”
“No.
It must be hundreds of times beyond a lethal dose.”
Kiyohiko inhaled deeply, forcing himself to endure the stench that made his head spin.
He did not release her wrist.
Instead, his grip tightened, as though he feared she might shatter the moment he let go.
“Shinobu Kocho, you’re a doctor, aren’t you?”
“What kind of doctor does something like this to herself?”
“Are you trying to kill demons, or are you trying to kill yourself first?”
Shinobu stared at him.
There was no hatred of a Demon Slayer within his eyes, nor the fear of prey confronting its predator.
There was only pure, incomprehensible concern.
The kind of expression an ordinary person might wear upon seeing a madwoman dancing at the edge of a cliff.
Shinobu fell silent.
For the first time, she saw an expression of genuine anguish upon a demon’s face.
After a long silence, the curve of her lips slowly disappeared.
Her eyes became deep and cold.
“What an impressive nose you have, Demon-san”
Her voice was quiet, yet chilling enough to reach the bone.
“Since you know it is poison, shouldn’t you release me?”
“If it seeps through your skin, it might melt such a kind little demon away.”
Kiyohiko ignored the icy warning.
Patients became emotional sometimes.
He had long since grown accustomed to it.
In his previous life, he had once tried to delicately inform a patient that there was a problem with a particularly sensitive part of his body—and the man had chased him halfway around the examination room.
In the next instant, Kiyohiko’s grip around Shinobu’s wrist abruptly tightened, and the blood within his body began flowing in reverse.
Shinobu blinked.
A strange sensation spread through her hand, as though an invisible tube were drawing away her flesh itself.
“You—”
Her pupils contracted.
Before her eyes, the cut across her left palm healed in the space of a single blink, as though time itself had reversed.
The skin knitted back together, the dried blood peeled away, and not even the faintest scar remained.
Her hand returned to its original pale appearance, its skin somehow seeming even smoother than before.
At the same moment, however, a suppressed groan escaped Kiyohiko’s throat.
“Ghk… This one certainly packs a punch…”
He abruptly released Shinobu’s wrist and staggered half a step backward as though he had received an electric shock.
Then he raised his right hand and deliberately held it between them.
A cut had appeared across his previously unblemished palm.
It was identical to the wound Shinobu had carved into her own hand, matching its position and depth perfectly.
But that was not the truly frightening part.
Under normal circumstances, a wound so minor would heal within a single breath for any demon—especially one with Kiyohiko’s extraordinary regenerative ability.
Yet even now, the cut showed no sign of closing.
Instead, the flesh around it had turned an unnatural shade of blackish purple.
A faint sizzling sound emerged from the wound as wisps of white smoke rose into the air, as though someone had poured strong acid directly over his skin.
“Do you understand now, Miss Shinobu?”
Kiyohiko held her gaze, his expression more serious than she had ever seen it.
“You should know what this means for your body.”