Before they set out, Urokodaki-sensei opened a cabinet and took out two fox masks.
They were protective masks he had carved by hand—meant to ward off misfortune for the ones who wore them.
"Aoyama. Tanjiro. These are protective masks… put them on."
The last time he had handed out masks like this, the children who wore them had never returned.
Aoyama stepped forward and accepted his mask, his expression unusually serious.
"Don't worry. We'll come back alive. Both of us."
Urokodaki nodded heavily.
His gaze lingered on Aoyama's face. This child possessed sharp perception. In the future, he would undoubtedly accomplish something extraordinary.
Nearby, Tanjiro was trimming his hair neatly.
Aoyama returned to sit by the hearth, watching him for a moment before asking casually,
"Hey, Tanjiro. Do you know how demons are classified?"
Tanjiro hesitated. Weren't they just man-eating demons? Was there really a difference?
Aoyama poked at the firewood, sparks flickering.
"Humans get stronger when they eat their fill. Demons are the same—their strength depends on how many humans they've devoured."
"So… the more people they eat, the stronger they become?" Tanjiro responded.
Urokodaki, who was folding the new robes prepared for them, glanced approvingly at Aoyama. This was something he had intended to explain himself. Now Aoyama was doing it in his place.
"Exactly," Aoyama nodded. "The more they eat, the more powerful they become. Some can even alter their bodies. Some develop strange abilities."
Tanjiro's heart trembled.
This world was far more complicated than he had imagined.
At dawn—
Aoyama donned the new robe Urokodaki had prepared.
In the other room, Tanjiro was saying goodbye to Nezuko.
At Aoyama's waist hung the Nichirin Blade given by Urokodaki. His gaze drifted to the wooden sword resting on the rack.
After a brief pause, he picked it up as well and tied it to his belt.
"You two go attend Final Selection without worry," Urokodaki said during their final farewell. "I'll take care of Nezuko and wait for your return."
Tanjiro ran a few steps ahead before turning back and waving.
"Urokodaki-sensei! Please give my regards to Sabito and Makomo!"
The moment the words left his mouth, Aoyama clearly saw Urokodaki's body stiffen.
Without hesitation, he grabbed Tanjiro's arm and bolted down the mountain.
"W-wait! Senior Brother Aoyama, why are we suddenly running?"
After finally stopping, Tanjiro gasped for air.
Aoyama leaned against a large tree, arms crossed.
"You idiot. Didn't you notice how Sabito and Makomo were different from us?"
"D-different? How?" Tanjiro froze.
Aoyama sighed softly.
Of course he hadn't noticed.
"Sabito and Makomo are already dead. They were killed during Final Selection. What you saw were their spirits."
"By seniority… they were our senior brother and sister."
Tanjiro felt a chill run from his feet to his scalp.
So that was it.
During all that time they guided him, Urokodaki-sensei had never once mentioned them.
Even Senior Brother Aoyama had remained silent.
…
Mount Fujikasane.
They arrived at the site of Final Selection.
The mountain was covered in blooming wisteria flowers—despite it not being their season.
At the entrance stood two young girls with identical faces but different hair colors, calmly explaining the rules.
"Within Mount Fujikasane are demons captured alive by Demon Slayers."
"They cannot leave."
"Because from the foot to the mid-slope of the mountain, wisteria flowers bloom year-round—the very flowers demons detest."
"Beyond this point, however, there are no more wisteria… and demons will roam freely."
"Survive here for seven days. That is the condition for passing Final Selection."
They finished their explanation in alternating voices, then together said, "We wish you good fortune," before walking away with wisteria lanterns in hand.
Final Selection had begun.
Beside him, Tanjiro took a deep breath.
He was ready.
"Tanjiro. Protect yourself."
With only that brief instruction, Aoyama vanished into the forest at high speed.
For him, this place was paradise.
A mountain full of demons, all gathered conveniently in one location.
Much better than hunting them one by one near Mount Sagiri.
Tanjiro opened his mouth to speak, but Aoyama's figure had already disappeared.
He had thought they would stick together.
Instead, they parted ways immediately.
"Senior Brother Aoyama… see you in seven days!"
Though the man was long gone, Tanjiro still waved in the direction he had vanished.
Aoyama's goal was simple.
Slay demons.
Kill the Hand Demon.
Avenge Sabito. Avenge Makomo. Avenge them all.
He hadn't gone far when a strange noise echoed behind him.
He stopped.
Closing his eyes slightly, he focused, letting his sharpened hearing pinpoint the source.
Behind him.
To the right.
His eyes snapped open.
His hand swiftly drew the wooden sword from his waist.
With Total Concentration—Breath of Light—
A wooden blade was more than enough for these small fry.
"Gah—gah—gah—!"
"Finally! A human! I'm starving!"
A grotesque demon crawled out, six limbs scraping against the ground.
Six limbs—because two extra arms protruded grotesquely from its abdomen.
Aoyama narrowed his eyes slightly.
"A lower-level demon."
The demon glanced at the wooden sword in Aoyama's hand. Blood still stained its mouth from its last meal.
It burst into cackling laughter.
"Brat! Even those with Nichirin Blades couldn't hurt me. What can a broken wooden sword do?"
"Once I eat you, I'll grow even stronger!"