Insect Breathing

After lunch, the Tsuguko at the Butterfly Mansion, Kanao included, stared blankly at the mountain of bowls and dishes piled on the table.

Kanae smiled and stroked their little heads. "Go play. We'll clean up here."

Genya shoveled the last mouthful of rice into his mouth, stacked his bowl on his teacher's pile, and carried the bowls over to the washbasin with his cheeks still bulging.

"I should help..."

Kanao's eyes always looked vacant, as though the artist had forgotten to add the highlights.

"Go on. If you don't want to play, go take a nap. Kids your age need plenty of sleep to grow." Haruto ruffled Genya's hair. "Want to go find your brother?"

Genya's eyes lit up, but he glanced hesitantly at the basin overflowing with dishes. "I should wash the bowls first..."

"Oh, just go already."

After shooing Genya away, Haruto rolled up his sleeves and found a folding stool to sit on as he washed the dishes, his long legs sticking out to one side. "What's going on with that child?"

Kanae looked up from putting away the leftover food. "Kanao?"

"Yeah. She's so slow to speak."

Shinobu rolled up her sleeves and crouched beside him to help wash the dishes. "Kanao... didn't have a happy childhood," she said softly. "That may be why she's rather withdrawn, but she's a good child."

"Like Genya? His looks tend to give people the wrong impression, but he's a good kid."

Kanae didn't want to dwell on that subject and steered the conversation elsewhere. "Miss Tamayo is developing a new drug to improve swordsmen's physical abilities."

Haruto raised an eyebrow.

Tamayo had been contacting him more frequently lately, and she had indeed mentioned a new drug in her letters.

But the drug was intended to do more than improve swordsmen's physical abilities. Using Genya's blood after his demon transformation, she hoped to develop a drug that would allow people to heal as quickly as demons while retaining their humanity.

In her vision, once the drug was successfully developed, members of the Demon Slayer Corps would be able to maintain their fighting strength against demons and suffer fewer losses in battle.

But that was easier said than done. Aside from the many difficulties involved in developing the drug, even testing its effects would be extremely difficult.

Clinical trials required the participation of swordsmen or ordinary people, and Kagaya would never let Tamayo experiment on the swordsmen.

"This drug is extremely dangerous. Ordinary people may not be able to withstand it."

Tamayo's letter was filled with helpless frustration, but there was nothing she could do. "The project will have to be shelved for now. I should focus on developing a drug to use against Muzan instead."

Precisely because it was dangerous, Haruto didn't want her considering the Demon Slayer Corps' swordsmen as test subjects.

"Why, did Miss Tamayo discuss this drug with you?" he asked with feigned casualness.

"No. It only came up while we were discussing the proportions of poison in Shinobu's Nichirin Blade," Kanae said. "Although Shinobu might need the finished drug, even Miss Tamayo admitted that the risks were too great and she wouldn't continue researching it."

At the mention of poison, Shinobu Kocho lowered her head slightly as she washed the dishes.

Haruto gave it a moment's thought and understood what was on her mind.

It was probably something along the lines of, Everyone else can cut off a demon's head easily. I'm the only one who has to rely on poison.

So he pretended not to notice and asked Kanae instead, "How's the development of your Flower Breathing forms coming along?"

Kanae had been studying a new Breathing Style based on Water Breathing for some time. A year ago, she had made a breakthrough and named it Flower Breathing, which was also why she had been given the title of Flower Hashira.

"There are six forms so far."

"And you've mastered them all too?" he asked Shinobu Kocho.

"More than that." Kanae laughed softly, pride filling her voice. "Shinobu has not only mastered every Flower Breathing form, she's even devised Breathing Style forms better suited to herself."

"Oh!" Haruto drew in a sharp breath and turned to Shinobu Kocho. "So you're a genius too!"

The purple-eyed girl brushed the stray locks from her face with her wrist, looking a little awkward. "I just had a few ideas based on Flower Breathing..."

"Go get your sword and show me. I'll help you gauge how powerful your Breathing Style is."

Haruto quickly finished washing all the bowls and emptied the dirty water. Shinobu Kocho then emerged with her Nichirin Blade, looking rather shy.

Her Nichirin Blade had been personally forged by Tetsujikawara Tecchin, the chief of the Swordsmith Village, who specialized in crafting unusually shaped blades. Its peculiar blade was slender and sharp, somewhat like a hooked needle. A poison reservoir inside the sword allowed her to inject wisteria poison into demons when she attacked.

Shinobu Kocho stood among the flowers in the courtyard, sword in hand. Facing her sister's comforting smile and Haruto's inquisitive gaze, she gradually felt the tension in her chest ease.

The girl's entire presence changed the moment she gripped her sword.

"Then... what should I use as my target?" The corners of her lips rose slightly. "An insect's dance can't reach its full power without a target."

Haruto ran his tongue over the corner of his mouth, then turned and picked up his own Nichirin Blade.

"Just... use me as your target."

Shinobu's eyes suddenly widened. A nimble butterfly seemed to flit through those deep purple irises.

"Be careful, Haruto." Shinobu Kocho's hand flicked rapidly, creating a dazzling shimmer of blade light. "Butterflies are very fast!"

Before she had finished speaking, she leaped lightly into the air, her slender body soaring. Her Haori, similar to Kanae's, made her look like a fluttering chestnut tiger butterfly.

Shinobu Kocho was incredibly fast, exploiting every advantage of her build at that moment.

Whoosh!

Haruto caught a faint sound and spun around, but the butterfly was nowhere in sight.

"Insect Breathing: Butterfly Dance..."

The airy voice drifted into his ears, and a swarm of fluttering butterflies appeared before his eyes. Shinobu Kocho swooped out of their midst, her blade flashing like snow!

"Caprice!"

Haruto immediately twisted his hand at an odd angle and brought his blade across his body. With a clang, her sword tip struck his blade hard enough to numb the web between his thumb and forefinger!

So fast!

If the sense of danger he had honed in battle hadn't prompted such a quick reaction, he might have embarrassed himself in front of the Kocho Sisters!

When her first strike failed, Shinobu Kocho immediately flipped behind Haruto. Her butterfly sleeves fluttered as she unleashed several rapid thrusts.

"Dragonfly Dance: Hexagonal Compound Eyes!"

"Whoa!"

Haruto twisted his mouth, turned, and grabbed the end of the Nakago in a reverse grip. Just as he had done against Lower Rank Four, he swept his sword around in front of him, throwing up a fan-shaped shield of blue-violet blade light.

The lightning-fast point struck the blade shield. The light in Shinobu Kocho's eyes dimmed slightly, and she swiftly pulled back.

Her slight, short figure darted through the flowers, making Haruto frown.

Star Breathing already emphasized speed, yet Shinobu Kocho was even faster. In developing her Breathing Style, she had pushed her natural speed advantage to its limit!

What else was Shinobu good at? Haruto remembered. Was it... thrusting?

The thought flashed through his mind, and the pointed blade was already before his eyes!

"Bee Sting Dance: Pulling Stab!"

Haruto's heart tightened. He could have used his muscular strength to twist out of the way, but as he saw the sword tip, he also caught sight of Shinobu's eyes.

Those clear purple eyes held a measure of uncertainty and a measure of determination, and even her face was taut.

Something stirred in Haruto's heart, and he reacted in an instant.

He twisted his body, narrowly avoiding the pointed blade.

With the sound of tearing fabric, the sword tip ripped a long slash across the chest of Haruto's Haori.

"Oh!" Kanae exclaimed, though inwardly she felt as if an enormous weight had been lifted.

Haruto covered his chest and said with feigned annoyance, "How are you so fast? This outfit is a family heirloom. You'll have to pay for it."

Shinobu touched down on her toes and came to a steady stop, looking a little bewildered.

"Am I... really that fast?"