Chapter 1
How it began
The first time Zenitsu Agatsuma met Tanjiro Kamado, he was crying.
Loudly.
Desperately.
Clinging to a girl who very clearly did not want to marry him.
“PLEASE! I’LL BE A GOOD HUSBAND, I SWEAR—”
“Let go of me!”
And then—
“Hey, are you okay?”
Zenitsu turned.
Everything stopped.
Tanjiro stood there, gentle eyes filled with concern, his voice soft but steady. Like nothing in the world could shake him.
Zenitsu blinked.
“. . .Huh?”
“Are you hurt?” Tanjiro asked, stepping closer. “You look really stressed.”
“I— I—”
Zenitsu forgot how to speak.
It didn’t hit him fully until later. At the mansion.
After the danger had passed.
After the fear settled.
Tanjiro smiled at the children they had saved. It wasn’t forced. It wasn’t dramatic.
It was just. . . real.
Warm.
Like sunlight slipping through a window.
Zenitsu’s chest tightened.
His face burned.
‘What is this?’
He grabbed his shirt, pressing his hand against his racing heart.
‘This feeling. . . I know this feeling. . .’
His breath hitched.
‘This is the same one I get when I look at girls. . .’
A pause.
Then—
“. . .Wait.”
His eyes widened.
“. . .Does that mean—”
From that moment on. . .
Things were never the same.
As for Inosuke Hashibira—
He didn’t think about it that much. He just noticed things. Like how Tanjiro always stood his ground.
How he smelled like warmth and something calm.
How fighting him felt. . . exciting.
“. . .You’re weird,” Inosuke muttered one day. Tanjiro blinked. “Huh?” “I wanna fight you again.” Tanjiro smiled. “We just fought.” “Yeah. Again.” “Okay?” Inosuke crossed his arms, looking away. “. . .And stay close.” Tanjiro tilted his head. “Why?” “. . .Because I said so!”
He didn’t understand it.
But something about Tanjiro made him want to stay.
Then came the Hashira meeting.
Tanjiro was there in the courtyard, tied up and with bruises, nervous but determined.
He looked up.
And saw them.
All of them.
Strong. Intense. Overwhelming.
His brain short-circuited.
And then—
He fainted.
Silence.
“. . .Did he just—?” Giyu Tomioka murmured.
“Ara ara. . . I think he fainted because of us,” said Shinobu Kocho, crouching beside him. “Why would he faint—oh. Ohhh.” Kyojuro Rengoku blinked. Realization spread like wildfire. “Well! That must mean we are extremely flamboyant!” declared Tengen Uzui proudly. Tanjiro woke up just in time to see Sanemi Shinazugawa threatening Nezuko.
Everything after that happened fast. “Get away from her—!”
CRACK.
Sanemi hit the ground.
Hard.
Everyone froze.
“. . .That kid’s strong,” someone muttered.
Later. . .
Inside the Butterfly Mansion, the night settled in like a slow exhale.
Lanterns flickered softly, casting warm gold across the wooden room. The Hashira were gathered, some seated, some standing, all pretending they were simply “resting.”
“This is boring,” Sanemi Shinazugawa muttered, arms crossed. “Why are we all here again?”
“To recover,” Shinobu Kocho replied calmly. “Though clearly some of you don’t know how to relax.”
“Tch.”
“I think it’s nice!” Mitsuri Kanroji said, smiling brightly. “It feels peaceful!”
“Peaceful is boring,” Sanemi shot back.
“Not everything needs to be loud and violent,” Obanai Iguro added, glancing at him.
“You wanna say that again?”
“Gladly.”
“I think something flashy would improve this greatly,” said Tengen Uzui, leaning back.
“I agree! A lively atmosphere is important!” Kyojuro Rengoku added enthusiastically. “. . . It’s fine like this,” Giyu Tomioka said quietly.
Sanemi groaned. “Of course you’d say that.”
“. . .Nothing is happening,” Muichiro Tokito murmured, staring at the ceiling. “That’s the point,” Obanai said. “. . .I forgot what the point was.” “Of course you did. . .”
Then—
Laughter.
Bright.
Clear.
Coming from outside.
Everyone went still.
“. . .Did you hear that?” Mitsuri asked, already sitting up straighter. “That’s not subtle,” Sanemi muttered. “It came from the garden,” Giyu said, already standing. Shinobu smiled slightly. “Well. . . aren’t you all curious?” No one answered. But everyone moved.
The door slid open.
Cool night air drifted in.
And the moment they stepped outside—
They froze.
The garden was dim, lit only by fire lamps glowing softly in the dark. Rain fell gently, shimmering in the light. And in the middle of it—
Tanjiro Kamado laughed.
“Nezuko, over there!” he called, running across the wet grass. Nezuko darted past him quickly. “HEY! THAT’S NOT FAIR!” Zenitsu Agatsuma shouted, slipping slightly. “I’M GOING TO FALL—WAIT—!” “YOU’RE TOO SLOW!” Inosuke Hashibira yelled, charging straight through the rain. “I’M WINNING!” They were playing tag. In the rain.
At night.
And Tanjiro—
Tanjiro was glowing.
Silence fell behind the Hashira.
Not a single one of them spoke.
“. . .He looks happy,” Rengoku said softly. “. . .Too happy,” Sanemi muttered, though his eyes didn’t leave Tanjiro. Uzui exhaled slowly. “. . . That’s dangerously flashy.” Muichiro blinked. “. . .He looks. . . nice.”
Giyu said nothing.
But he didn’t move.
Shinobu glanced around.
Then smiled.
“My, my. . . what an interesting reaction.”
No one answered.
“. . .You’re all staring,” she added lightly. “I’m not staring,” Sanemi snapped immediately. “Of course not,” Obanai said dryly. “You’re just glaring very intensely.” “Tch.” Mitsuri clasped her hands, eyes shining. “He’s so cute! Look at him smiling like that!” “Kanroji,” Obanai muttered. “What? It’s true!” Shinobu’s eyes slid toward Giyu. “And you, Tomioka-san?” “. . .What about me?” “For someone who claims to be indifferent. . .”
A pause.
“. . .You haven’t looked away once.” Giyu stiffened slightly.
“I have.”
“You haven’t.”
“. . .I have emotions.”
Sanemi snorted. “That’s news.”
Outside—
Tanjiro spun slightly, laughing as Zenitsu tripped again. “Zenitsu, are you okay?” he called. “I’M NOT OKAY, I’M DYING—!” “You’re not dying,” Inosuke snapped. “GET UP!” Nezuko tapped Tanjiro’s shoulder and ran again. “Ah—hey!” Tanjiro laughed, chasing her. Rain clung to his hair.
To his lashes.
And still—
He smiled.
Behind the doorway, something shifted.
Hearts beat faster.
Breaths caught.
No one wanted to say it.
“. . .This is bad,” Sanemi muttered under his breath. “What is?” Mitsuri asked innocently. “. . .This.” He gestured toward Tanjiro. Uzui nodded slowly. “. . .Yeah. This is a problem.” Rengoku pressed a hand to his chest. “My heart is beating quite strongly!” Muichiro blinked. “. . .Mine too.”
Shinobu covered a small smile. “How fascinating.”
Then—
Tanjiro stopped.
“. . .Huh?” He turned slightly, nose twitching. “. . .That’s strange.” Zenitsu froze. “WHAT!? WHAT IS IT!? IS THERE A DEMON!?” “No, no,” Tanjiro said. “I just. . . smell something.”Inosuke crossed his arms. “What kind of smell!?” Tanjiro hesitated. “. . .It’s warm.”
Everyone froze.
“. . . And kind of nervous.”
Silence.
Zenitsu turned red instantly.
Inosuke looked away.
Behind them—
The Hashira stopped breathing.
“. . .It’s coming from—”
Tanjiro turned toward the house.
“Move,” Obanai whispered sharply.
“Now,” Sanemi added.
“MOVE!” Uzui whispered sharply.
In a split second—
They vanished.
Back inside.
Out of sight.
Gone.
Tanjiro blinked.
“. . .Huh?”
He stepped closer, looking around.
“. . .Weird. . .”
Zenitsu ran up beside him. “WHAT WAS IT!? ARE WE SAFE!?” “. . .Yeah,” Tanjiro said slowly. “I think I imagined it.” Inosuke scoffed. “Your nose is broken.” “It is not!”
“It is!”
Inside the room—
No one spoke at first.
Then—
“. . .I almost had a heart attack,” Rengoku admitted. “That was close,” Uzui added. “He almost caught us!” Mitsuri whispered. Shinobu smiled. “Yes. . .”
A small pause.
“. . . very interesting.”
All eyes slowly turned—
Toward Giyu.
He stood still.
Very still.
“. . .What?” he said. Sanemi smirked slightly. “You didn’t blink once.” “I did.” “You didn’t.” “. . .I have emotions.”
No one believed him.
Outside—
Tanjiro laughed again.
Unaware.
Inside, hearts refused to calm.
And from that moment on. . . Nothing was the same.
Far away, watching everything unfold with quiet awareness. . .
Kagaya Ubuyashiki smiled gently.
“. . . I see.”
A pause.
“. . .This could become. . . complicated.”
So he made a decision.
If they insisted on staying near Tanjiro. . .
He would simply make it official.
