Chapter 427: Might Be Worth Studying
Once his Observation Haki had swept through the whole scene, everything clicked into place — Ryū understood exactly where in the timeline he'd landed: the very early hours of the night Tanjirō's family had been slaughtered.
For some unexplained reason, Tanjirō had decided not to stay overnight at the base of the mountain as he normally would, choosing instead to head home in the middle of the night.
By that point, his family had already been dead for at least several hours.
And, to make matters worse, on his way back up the mountain, Tanjirō had run into a demon — a mere underling, per the invitation quest's own description.
The demon he'd stumbled onto clearly wasn't Demon Slayer's actual final boss, Muzan. If it had been Muzan himself, this whole invitation quest probably wouldn't have even had time to trigger — Tanjirō would already be dead.
Because at this exact point in the timeline, Tanjirō wasn't yet the Demon Slayer Corps member capable of standing against an Upper Rank demon. Right now, he was just an ordinary charcoal seller — a little tougher than average, sure, with a slightly harder skull than most, but nothing more than that.
Ryū's figure vanished from where he stood, reappearing an instant later just a short distance from Tanjirō, the newcomer at the center of this quest.
At that exact moment, Tanjirō — a charcoal basket still strapped to his back — stood gasping for breath, axe raised, eyes locked in terror on the "hideous monster" in front of him.
"Hideous" wasn't an exaggeration, either — the thing's face was genuinely grotesque, uglier even than your average zombie.
"This... this must be the demon that old man was talking about. There really are demons up here on this mountain... and no matter how many times I hack at it with this axe — even cutting its arm clean off — it just regenerates almost instantly."
"And worse still, I'm hurt now. Feels like one or two of my ribs are broken, and my left hand's got a gash from its claws that won't stop bleeding."
Axe in hand, Tanjirō breathed heavily, sweat beading across his forehead despite the dead of winter.
Tension hung thick in the air around him. Staring down the "demon" barely a dozen meters off, he gritted his teeth.
Running wasn't an option — not with injuries like these. Even at full health, he doubted he could outrun the thing; he'd already tried, and failed.
Was this really it? Was he actually going to get eaten by a demon tonight?
Something that simply refused to die no matter how many times he cut it down — there was nothing he could do against that, nothing at all.
Just as Tanjirō's nerves stretched to their breaking point, something flickered at the edge of his vision — a blurry, indistinct silhouette.
He turned, startled, and spotted an unfamiliar young man walking calmly toward him, entirely unhurried.
The snow underfoot was thick, deep enough to swallow a boot whole, and yet this stranger's steps left it completely undisturbed — as if his body carried no weight at all.
Not that Tanjirō registered that particular detail. All he registered was another person walking straight into danger, and his stomach immediately dropped.
He shouted, urgent, at the approaching stranger. "Stay back! It's dangerous here! That thing's a demon — it eats people!!"
The moment the words left his mouth, Tanjirō felt a stab of regret. Hadn't he just drawn the demon's attention straight to this stranger?
Sure enough, the demon's gaze immediately shifted toward the newcomer.
Its grotesque face twisted into a leering, revolting grin. "And here I thought a scrawny charcoal seller was all I'd get to satisfy my appetite tonight. Didn't expect a soft, pretty-faced sissy to come wandering in too."
The moment that grating voice finished speaking, Tanjirō noticed the approaching stranger pause slightly, mid-step — as if he'd actually heard it.
Sure enough — Ryū had heard every word of it clearly. It had been a genuinely long time since he'd run into someone this determined to get himself killed.
He was just a passerby, minding his own business, and now he was getting slapped with the nickname "sissy"?
And what exactly was so offensive about having decent skin, thanks to years of physical training?
Or having a fairly attractive face, courtesy of solid parental genetics?
Was that really grounds for "sissy"? Did this thing not have functioning eyes?
His face twitching slightly, Ryū continued walking, step by step, toward the demon.
Before he could close the distance, though, a small figure suddenly darted into his path — Tanjirō, axe still raised.
Tanjirō stepped directly between Ryū and the demon, urgent. "This thing really is a demon. Please, get out of here — otherwise we're both going to end up in serious trouble."
Ryū's Observation Haki swept over him in an instant, taking full stock. "You're pretty seriously hurt already, aren't you. Three broken ribs, a fourth with a hairline crack. Some cracking in your left leg too, plus that gash on your left hand. And bruises everywhere, on top of it."
Tanjirō blinked, asking on pure instinct, "How do you even know how many ribs I broke... wait, that's not the point right now — the point is, this demon is genuinely dangerous!"
Ryū stepped past him, coming to stand beside him instead, his tone perfectly calm. "This 'demon' you're talking about — you mean this ugly thing right in front of us?"
Before Tanjirō could even nod, a thin, near-invisible slash of compressed air tore through the air, sweeping forward with unstoppable force.
In an instant, faster than the eye could track, the grotesque demon was cleaved cleanly in half.
"This... this is... what just happened?"
Tanjirō's eyes went wide, staring at the scene in front of him in total disbelief.
The demon he'd been utterly unable to kill, no matter what he tried — the very thing that had hurt him this badly — had just been split cleanly in two, without warning.
Just then, Tanjirō heard the unfamiliar young man's voice again. "Huh? Even that doesn't do it in? Demons are genuinely a novelty. Maybe I should catch one for Wolffy to study."
Study? A demon??
Tanjirō's expression stiffened slightly. Studying a demon — what kind of operation was that supposed to be?
Could demons even be studied like that?
Were city folk really this bold these days?
"Eh, never mind — too ugly, not worth studying anyway. Since a compressed air slash won't finish it off, guess I'll just vaporize it instead."
A flash of deep blue light streaked past, striking the halved demon dead center.
Before Tanjirō could even process what was happening, a terrifying explosion of energy erupted without warning.
A devastating shockwave swept outward, tearing the snow blanketing the ground up into the air in every direction.