Those words were very soft, but they were like a small pebble thrown into a calm lake, causing a ripple to spread through her heart.
She looked at the serious eyes of the young man before her.
There was no mockery in those heterochromatic eyes, no calculation, only a pure, almost stubborn determination.
She suddenly remembered that moonlit night, the scene of him standing in front of her, his chest pierced by a demon’s claw…
“…Is that so?” Kochou Shinobu’s voice was a bit lower than usual.
She looked away, putting on her smile again.
“But it’s a pity, my Insect Breathing isn’t suitable for Ippū-san~”
She turned around, her back to him, her voice returning to its usual lighthearted tone:
“Insect Breathing was something I created to compensate for my lack of physical strength. You see, I’m only 151 centimeters tall and weigh only 37 kilograms. I’m a very small girl~”
She turned her head slightly, her eyes crinkling at the corners.
“A body like this can’t use other mainstream Breathing Styles, which is why I need to rely on Wisteria Toxin and win through speed and technique. Ippū-san’s height, frame, and foundational strength are completely different from mine. Forcing yourself to learn Insect Breathing would actually limit your potential.”
Hanayuki Ichika nodded.
This explanation was reasonable; he had actually guessed as much.
In the original work, Kochou Shinobu’s Breathing Style was indeed a specialized style tailored for her.
“However~” Kochou Shinobu suddenly turned back around and said with a smile,
“Although I can’t teach you Insect Breathing, I can give you some guidance on the basics of ‘Total Concentration: Constant’. After all, no matter the Breathing Style, the foundation is the same.”
She walked to the tatami mat on the inner side of the entrance, sat down elegantly in seiza, and then patted the spot next to her.
“Come, sit here.”
Hanayuki Ichika was a bit surprised, but he did as he was told and sat down facing her.
They were very close.
Close enough that he could clearly see her long eyelashes, the fine sweat on the tip of her nose, and her cheeks slightly flushed from the recent exercise.
And there was that familiar, faint scent of wisteria flowers mixed with a sweet body fragrance, lingering around his nose once more.
He couldn’t help but want to say…
“Kochou, you smell so good!”
But he was afraid that the mischievous Kochou Shinobu would tease him and refuse to teach him…
Then, Kochou Shinobu began to explain the essentials of Total Concentration Breathing: how to adjust the breathing rhythm, how to deliver oxygen to every cell in the body, and how to temporarily enhance physical functions through breathing.
Her voice was gentle and patient.
As she explained, she demonstrated the depth and rhythm of the breaths.
Hanayuki Ichika tried his best to focus on listening.
But that fragrance and the face so close to him still made his heart beat faster uncontrollably.
“Your breathing should be steady, don’t let it get messy.”
Kochou Shinobu suddenly stopped her explanation, her purple eyes looking at him intently.
“Ippū-san, your heart… is beating quite fast.”
As she spoke, she actually leaned in slightly and pressed her ear gently against his chest.
“Thump, thump, thump…”
The clear and rapid heartbeat could be felt through his clothes.
Kochou Shinobu held this posture for a few seconds, then straightened up, covering her mouth with her sleeve and letting out a light giggle.
“Oh my, oh my~ It really is fast. I didn’t expect that a demon could also have a rapid heartbeat like a human. How interesting~”
Her eyes curved into crescents, her tone clearly teasing.
Hanayuki Ichika’s face turned red instantly.
He opened his mouth, wanting to defend himself, but found himself at a loss for words.
Facing this beautiful, charming, gentle yet mischievous girl,
Kochou Shinobu admired his embarrassed look for a moment before leisurely changing the subject.
“Speaking of which, Ippū-san, there’s something I’ve been curious about.”
“W-What is it?”
“During the trial earlier, you said you stole and ate the wisteria cakes I made.”
Kochou Shinobu rested her cheek on her hand, tilting her head to look at him, her smile filled with inquiry.
“First of all, after a demon becomes a demon, their physiological structure changes. Eating human food causes extreme disgust and nausea—you should have experienced that by now, right?”
Hanayuki Ichika nodded, remembering the churning sensation in his stomach when he had forced himself to swallow the cakes.
“Secondly,” Kochou Shinobu continued, her voice becoming even softer,
“I added a significant concentration of Wisteria Extract into those cakes. For a demon, that’s not just ‘bad-tasting,’ it’s a toxic substance that brings about burning pain. And yet you…”
She leaned forward slightly, the distance between them shortening again.
“You ate them all. Why?”
Her gaze was locked firmly onto Hanayuki Ichika, as if she wanted to look through his eyes and see his true thoughts.
Hanayuki Ichika met her gaze.
Her pupils were a deep purple, clearly reflecting his image at this moment.
He suddenly smiled.
It wasn’t an awkward smile, nor a concealing one, but a very faint, sincere smile.
“Because,” he said softly, his tone as calm as if he were stating a perfectly natural fact, “I wanted to taste the cakes you made yourself.”
“…”
Time seemed to stand still for a moment.
The smile on Kochou Shinobu’s face didn’t change, but those purple eyes widened almost imperceptibly.
She felt her heart—that heart that had beaten steadily in her chest for many years, long accustomed to using a smile to mask any fluctuation—suddenly and violently thud against her ribs.
“Thump!”
The sound was so loud she suspected he could hear it too.
Immediately after, her heart rate accelerated uncontrollably.
It was even faster than the one she had heard when pressed against his chest.
Blood rushed to her cheeks, and her breathing rhythm—that Total Concentration Breathing rhythm she had practiced countless times, which had long since become an instinct—actually showed a hint of disorder.
This feeling…
was very unfamiliar.
No, perhaps it wasn’t entirely unfamiliar.
In the past, when facing her sister Kanae, when she would gently stroke her head, when she would look at her with those same purple eyes full of smiles, her heart would also beat faster, and she would feel warmth and a fluttering sensation.
But the feeling now…
was somewhat different from then.
It was the same racing heart, the same disordered breathing, but there seemed to be something else mixed in, something more subtle.
A faint sourness?
A trace of inexplicable panic?
Or some kind of…
expectation that she didn’t dare investigate further?
She couldn’t say for sure.
Kochou Shinobu lowered her eyes, her long lashes casting shallow shadows on her cheeks.
She took a soft breath and then exhaled slowly, using the willpower she had honed over the years to forcibly suppress those surging unfamiliar emotions back into the depths of her heart.
“Oh my, oh my~” She lightly touched her slightly warm cheek with the back of her hand, her tone as light as if she were talking about the weather.
“Ippū-san really… knows how to tease a girl’s heart~”
She stood up and patted the non-existent dust from the hem of her kimono.
“But even so, I can’t teach you the Insect Breathing Style~” She turned and walked toward the courtyard, her voice drifting back with the wind.
“If only you were a bit shorter, your frame a bit more slender and delicate, if only you could become like a girl~ If you were to wear a beautiful and cute dress, I might consider taking you as my Tsuguko~”
As the last syllable fell, her figure had already glided several meters away like a real butterfly, disappearing to the other side of the courtyard in a few leaps.
Hanayuki Ichika sat alone on the entrance porch, staring in the direction she had disappeared for a long time without moving.
The afternoon breeze blew gently, bringing the fresh scent of the courtyard’s greenery.
He looked down and found a pale purple handkerchief left on the tatami—Kochou Shinobu must have used it to wipe her sweat earlier.
He hesitated for a moment, then reached out and picked it up.
The handkerchief was very soft and carried her unique fragrance.
He gently brought it to the tip of his nose, closing his eyes and inhaling softly.
That scent, a mixture of wisteria flowers and a young girl’s body fragrance, seemed to have some kind of magic that gradually calmed his heart.
Then, he sat upright with his legs crossed, carefully folded the handkerchief and placed it aside, and closed his eyes.
In his mind, he began to replay the essentials of Total Concentration Breathing that Kochou Shinobu had just explained.
Every inhale and exhale, the rhythm, the depth, and the resonance with the body…
At the same time, something deeper awakened in his consciousness—it was the reward granted to him by the system: “High Adaptability to Breathing Techniques.”
It wasn’t concrete knowledge, but an instinctive level of comprehension, a potential that allowed him to understand the essence of Breathing Styles and to deduce and create based on that foundation.
Insect Breathing wasn’t suitable for him.
So…
what kind of Breathing Style would suit him?
One that suited this body that had experienced death and rebirth, merging a demon’s constitution with a human’s will?
One that suited this desire to become stronger and protect those important to him?
Occasional birdsong came from the courtyard, and in the distance, the faint sounds of the Butterfly Mansion girls working could be heard.
Hanayuki Ichika was immersed in the depths of meditation, his breathing gradually becoming long and rhythmic…
The news that Hanayuki Ichika wanted to learn a Breathing Style somehow spread rapidly throughout the entire Demon Slayer Corps headquarters as if it had grown wings.
Initially, most people’s reaction upon hearing it was to scoff.
“A demon wanting to learn a Breathing Style? You’ve got to be kidding!”
“Breathing Styles are for killing demons! What does a demon want to learn it for? To commit suicide?”
“There’s definitely some conspiracy! Maybe he wants to figure out the weaknesses of Breathing Styles!”
“Shinobu-sama is far too kind, actually teaching him the basics of Total Concentration Breathing…”
Voices of doubt, disdain, and mockery echoed throughout the headquarters.
For these members who had dedicated their lives to the cause of hunting demons and shared blood feuds with them, a demon wanting to learn human combat techniques was not just absurd, it was almost a profanity.
The reactions of the Hashira varied, but most also held a skeptical attitude.
“A flamboyant idea, but I’m afraid it’s difficult to realize,” Tengen Uzui evaluated while stroking his chin.
“Namu Amida Butsu… Having such a deep obsession may not necessarily be a good thing,” Gyomei Himejima shook his head while weeping.
Rengoku Kyojuro was very direct: “Umu! Having a heart that strives for improvement is a good thing! But can a demon’s constitution really use a Breathing Style?”
Tomioka Giyu looked silently toward the Butterfly Mansion, his thoughts unknown.
As for the Wind Hashira Sanemi Shinazugawa, he exploded the moment he heard the news.
“Huh?! That demon wants to learn a Breathing Style?!” Veins popped on his forehead as he kicked over a training post.
“Are you kidding me! What does he think Breathing Styles are? A child’s game?!”
Behind him followed a group of members looking for excitement and several other startled Hashira.
The crowd quickly rushed toward the Butterfly Mansion…