The Tamahagane obtained during Final Selection would be forged by a specialized swordsmith into a blade meant exclusively for slaying demons.
That process would take about ten to fifteen days.
Once Tanjiro's body had mostly recovered, he resumed the daily training he used to do on Mount Sagiri. To prepare for future battles, he couldn't allow himself to grow rusty.
As for Aoyama—
He maintained his usual lifestyle.
During the day, he strolled about, waded into the river to catch fish and shrimp, adding a bit of wild flavor to dinner.
But after dinner—
That was the main event.
Nezuko would wake up, and he had to seize every moment to build their bond. He absolutely could not allow her to open her eyes and cling only to Tanjiro.
What sister spends her entire life following her brother?
If Nezuko was going to follow someone—
It should be him.
"Well rested? Want to go outside and look at the moon with me~?"
Aoyama asked with a bright smile.
Nezuko's soft pink eyes blinked gently, her lashes fluttering. Ripples spread through his heart.
Too cute.
Absolutely adorable.
"Mm…"
Nezuko instinctively turned her head toward Tanjiro.
In her consciousness, Tanjiro was her brother—her closest person. She naturally depended on him.
Aoyama shifted his body slightly, blocking her view.
"Hey, don't look at him. Around here, I'm in charge! Even Tanjiro listens to me~"
Behind him, Tanjiro called out pitifully,
"Senior Brother Aoyama~~~ Let me talk to my sister for a bit…"
Aoyama slowly turned his head.
A sharp, killing-intent-laced glance shot toward Tanjiro.
"You sure you want to talk?"
His tone was completely different from when he spoke to Nezuko.
Tanjiro swallowed.
He raised both hands immediately.
"It's fine! Senior Brother Aoyama, you chat with her first… I can wait…"
Aoyama nodded approvingly.
"Good. Sensible."
And just like that, Tanjiro watched helplessly as Senior Brother Aoyama led Nezuko outside to admire the moon, while he stood by the doorway, not daring to approach.
That killing intent earlier had been far too real.
Better to be cautious.
Behind him, Urokodaki stood silently, shaking his head slightly.
Tanjiro was being bullied so badly by Aoyama that even his sister had been "taken."
But this was a matter between young people.
No need for him to interfere.
He turned and went back to rest.
—
Fifteen days later.
A man in a long robe appeared, wearing a round hat adorned with small wind chimes. With every step he took, the chimes rang crisply.
Aoyama, who was lying on the large rock at the entrance sunbathing, saw the swordsmith approaching and sat up immediately.
"Hey, young man! Is this the residence of Sakonji Urokodaki?"
"I am Haganezuka. I've forged and brought the swords for Kamado Tanjiro and Aoyama Ren."
Aoyama leapt down from the rock.
"I'm Aoyama Ren. You've worked hard. Come in for some tea."
Haganezuka ignored the invitation and turned, pulling out the sword from his back.
"This is a Nichirin Blade. A Nichirin Blade I forged."
His hands moved continuously as he unwrapped the cloth.
"The raw materials come from the mountain closest to the sun—Scarlet Crimson Iron Sand and Scarlet Crimson Ore. They absorb sunlight and are forged into steel capable of killing demons…"
Aoyama smacked his forehead.
Right.
This man never listened to what others said.
He only talked about what he wanted to talk about.
A glint flashed in Aoyama's eyes, and the corner of his lips curved upward.
He stepped closer and saw the scabbard engraved with the words "Aoyama Ren."
He reached out and smoothly took it from Haganezuka's hands.
"I've received my blade. You may leave now. Kamado Tanjiro is about ten miles from here. If you hurry, you might reach him before dark."
Haganezuka finally paused mid-speech.
Without questioning it, he slung Tanjiro's sword over his back and immediately set off.
Inside the house, Urokodaki's upright posture tilted slightly.
He looked at Tanjiro.
"Why are you still sitting there? Go bring both the man and the sword back!"
Tanjiro rushed out at once, catching up to Haganezuka before he went too far and escorting him back.
When Aoyama stepped into the house, he walked straight into Urokodaki.
"Ridiculous."
Two simple words entered his ears.
Aoyama quickly defended himself.
"He doesn't listen to anyone! You heard me invite him in for tea, didn't you?"
Urokodaki sighed faintly, rubbing his forehead.
"He never listens to anyone."
The four of them sat together.
Haganezuka's excitement was barely contained.
"Quick! Draw your blades! The Nichirin Sword is also known as the 'Color-Changing Blade.' It changes color depending on its owner!"
Without hesitation, Aoyama drew his blade.
He was curious too.
What color would his sword become?
Red?
Yellow?
Green?
…Actually, let's hope not green.
That would be unlucky in a very specific way.
The blade began changing color from the base upward, visible to the naked eye.
Finally—
It settled.
The blade turned a brilliant crimson.
Not entirely.
Along the edge ran a delicate golden line.
As a ray of sunlight struck it, the blade shimmered faintly.
Aoyama smiled in satisfaction.
Not bad.
He liked this color.
Good thing it wasn't green.
"Red!" Haganezuka shouted excitedly, grabbing Urokodaki's arm and shaking it.
Urokodaki pointed calmly.
"Look closely. There's a golden edge along the blade."
Haganezuka leaned in so close he was nearly pressing his face against it.
"Strange… strange… I've never seen such a thing!"
He suddenly turned to Tanjiro.
"Boy! Draw your sword!"