The next day.
"Knock... knock, knock... knock, knock, knock."
"Teiichi, are you up?"
Kanon's voice from the doorway woke Teiichi from his sound sleep. He instinctively squeezed his eyes shut a few times, then slowly opened them.
Then he stretched out his arms and pushed himself up from the soft bed.
Teiichi let out a deep breath, as though trying to expel all the stale air that had accumulated in his chest.
Although he had only just woken up, he had not drifted into a hazy, half-conscious sleep until late last night, and even after falling asleep, he had slept poorly.
So now that he was awake, he felt indescribably exhausted.
Teiichi turned his somewhat stiff neck and looked toward the window.
A golden sun already hung high in the sky, its brilliant light spilling through the wooden window as birds chirped outside. Teiichi simply sat quietly on the edge of the bed, gazing blankly out the window.
The world seemed to have undergone some subtle, peculiar change in Teiichi's eyes. It seemed clearer.
As he began using Wind Breathing, it too seemed to feel different, flowing more smoothly.
Teiichi raised his right hand and examined it closely.
Was it because I had truly become part of this world?
Teiichi wondered.
"Are you up, Teiichi? It's time for breakfast."
The renewed call brought Teiichi back to reality from his daze. He turned toward the door and answered:
"All right, I'm up. Give me a moment. I'll be right out."
After answering Kanon, Teiichi looked out the window again and gently shook his head, as though trying to shake off certain worries.
He slowly stood, straightened his clothes, then pushed open the door and walked out.
Early that morning, Kanon had noticed that Teiichi's door was tightly shut. She understood that he might be feeling weighed down by yesterday's news of their master's death, which was why he had not gotten up yet.
With that thought, Kanon decided not to disturb him and to let him rest a little longer.
However, after preparing breakfast, she waited a long time without seeing Teiichi leave his room.
A trace of anxiety rose in her heart. She patiently waited a while longer, but there was still no sign of movement from Teiichi.
Finally, unable to contain her worry any longer, Kanon decided to knock and ask how he was doing.
When Teiichi finally opened the door, Kanon hurriedly looked him over.
The boy before her had messy hair, with uncombed strands of short black hair scattered across his forehead, somewhat different from his usual neat appearance.
Aside from that, Teiichi looked slightly more haggard than usual, but overall, nothing was particularly unusual.
Seeing this, Kanon finally relaxed.
The two sat down at the dining table. Breakfast was very simple today: plain porridge with a few small dishes of pickled vegetables, alongside a dozen or so boiled eggs.
Teiichi picked up his bowl, slowly sipping the hot porridge as he watched Kanon eat, his eyes full of tenderness. He said softly to her:
"Kanon, for the next few days, I'll be focusing on practicing a special technique-Total Concentration: Constant.
"Put simply, it means using a Breathing Style nonstop, twenty-four hours a day.
"So for the next few days, I'll sleep during the day and train on my own while I'm awake at night.
"Could you help keep an eye on me during the day and wake me immediately if you notice I've stopped using my Breathing Style?"
Hearing this, Kanon hurriedly said, "Teiichi, you can sleep at night as usual. I'll watch over you at night."
Teiichi shook his head, smiled gently at Kanon, and said softly:
"I didn't sleep well last night anyway, so I'll start catching up on sleep this afternoon. Besides, I'll get hungry training at night. Could I trouble you to prepare food for me during the day, Kanon?"
Kanon knew Teiichi was looking out for her and did not want her staying up late, but there was nothing she could do to change his mind. She could only nod and agree:
"Mm-hmm, no problem! Leave it to me."
Then she blinked her large eyes and asked curiously:
"Teiichi, why do you have to use a Breathing Style twenty-four hours a day? Won't that be exhausting?"
Teiichi swallowed the porridge in his mouth and slowly explained:
"While you're using a Breathing Style, your physical constitution improves too.
"The improvement is tiny, so small you can't notice it at all, but it does exist.
"And if you use a Breathing Style twenty-four hours a day through Total Concentration: Constant, even though the improvement is tiny, it builds up over time.
"That's enough to gradually give us demon slayers physiques beyond those of ordinary people, allowing us to stand against demons."
Kanon was a little surprised to hear that constantly using a Breathing Style could improve physical fitness, and blurted out:
"Then the earlier, the better! The sooner you learn Total Concentration: Constant, the greater the boost to your physical fitness."
Teiichi nodded in agreement and replied, "Yes, the earlier, the better."
After receiving Teiichi's confirmation, Kanon eagerly asked:
"Then why doesn't the Demon Slayer Corps train demon slayers from childhood? If children learned Total Concentration: Constant when they were little, wouldn't they be stronger when they grew up?"
At this question, Teiichi frowned slightly and gave Kanon a piercing glance before answering solemnly:
"A Breathing Style isn't as easy to master as an ordinary skill!
"It takes extraordinary talent to grasp its mysteries!
"Not just anyone is qualified to learn such a profound and unfathomable art!
"Besides, a Breathing Style places an enormous burden on the body!
"If you start training too young, your body won't be able to sustain its use for long.
"So it's best to wait until you're at least eleven or twelve, once your body has undergone its initial development, before trying to learn Total Concentration: Constant.
"Otherwise, forcing yourself to train could cause permanent, irreparable damage to your body!"
"Oh, so that's how it is..."
After hearing this, Kanon sighed, disappointment written all over her face.
She had been eagerly hoping to learn Constant as soon as possible, but now that she knew she would have to wait several more years before she could begin learning this wondrous technique, she could not help feeling a little dejected.
"Flap, flap~"
Just then, a faint, rapid flutter of wings suddenly came from the window.
Teiichi and Kanon turned toward it in unison.
A Kasugai Crow, its black feathers gleaming with a mysterious light, was flapping its wings as it flew toward them.
It landed nimbly on the windowsill and steadied itself.
The Kasugai Crow opened its beak and spoke in a low, hoarse voice. "In five days, Kakushi, collect the little girl. In five days, Kakushi, collect the little girl."
"Teiichi, what did that crow mean by Kakushi?"
Hearing the Kasugai Crow's call, Kanon felt puzzled. She turned to Teiichi beside her and asked, her face full of curiosity.
Teiichi patiently explained:
"The Kakushi are a support division of the Demon Slayer Corps. They handle things like guiding people, transporting the wounded, and cleaning up battlefields.
"The Kasugai Crow means that a member of the Kakushi will come in five days to take you to the Butterfly Mansion."
After answering Kanon's question, Teiichi turned to look at the Kasugai Crow and said softly:
"All right, I understand."
Then Teiichi looked the Kasugai Crow over a couple more times, hesitated, and asked:
"Have you had breakfast? Would you like some?"
Worried that the Kasugai Crow might not understand, Teiichi pointed at the dining table before him.
Hearing Teiichi's words, the Kasugai Crow tilted its little head, its gaze settling on the dining table, then opened its beak and cried:
"Too poor, won't eat. Too poor, won't eat."
At the Kasugai Crow's merciless appraisal, black lines appeared across Teiichi's face, and he said helplessly:
"It's better to eat something light first thing in the morning. Eating rich meat and fish all day isn't good for you."
However, the Kasugai Crow seemed to ignore Teiichi's explanation entirely. It hopped lightly and let out two more shrill cries:
"Too poor, won't eat. Too poor, won't eat."
Clearly, it was extremely dissatisfied with the food before it.
After calling out, the Kasugai Crow resolutely turned away, flapped its wings, and flew off.
It left Teiichi standing there alone, speechless, with black lines all over his face.
"Pfft~" Beside him, Kanon finally could not help laughing at the sight.
She thought the Kasugai Crow was simply adorable, and Teiichi's embarrassed expression also made it impossible for her to hold back her laughter.
As the laughter gradually faded into the air, Kanon's gaze slowly grew deep.
In five days, would I be leaving this place for the unfamiliar Butterfly Mansion?
She sat quietly for a while, as though trying to settle those complicated feelings, before finally speaking softly, a trace of uncertainty in her voice:
"Teiichi, what Breathing Style will I learn when I get to the Butterfly Mansion?"
Teiichi was briefly taken aback by her question, then recalled the descriptions of the Butterfly Mansion in the original work.
After a moment's thought, he slowly replied:
"You'll probably learn Flower Breathing."
"Flower Breathing?"
Kanon repeated the name, a flicker of curiosity and delight crossing her eyes.
The name seemed to possess a special magic, making her involuntarily imagine herself breathing and fighting as gracefully as a flower. Kanon could not help asking:
"It sounds so beautiful. Does it mean breathing like a flower?"
Teiichi gently shook his head and explained:
"It doesn't actually have a direct connection to the way you breathe.
"The Breathing Style is called Flower Breathing mainly because its moves are as beautiful and graceful as flowers.
"Every Breathing Style has its own unique moves and style, and Flower Breathing is known for its graceful forms and dazzling moves."
Kanon listened, entranced, as though already deeply captivated by that beautiful, mysterious Breathing Style.
She put down her chopsticks, propped her chin in both hands, and began imagining what she would be like after learning Flower Breathing.
Her eyes sparkled, as though she could already see herself blossoming like a flower in battle.
Seeing this, Teiichi chuckled and gently patted Kanon's head, as though she were a mischievous child:
"All right, stop daydreaming.
"You'll be able to learn Flower Breathing once you reach the Butterfly Mansion in a few days.
"For now, eat, or the food will get cold."