At the foot of Mount Natagumo
Zenitsu had been there for a while now, squatting at the edge of the road with his golden haori wrinkling against the knees he wouldn't stop hugging.
He was trembling.
"Waaaa... they just took off like that... left me behind like it was nothing..."
Every so often he'd look up toward the mouth of the mountain, where Tanjiro and Inosuke had disappeared a while ago, and his eyes would fill with tears all over again.
"They could've at least tried a little harder! A tiny bit of encouragement, was that too much to ask? If they'd just pushed me a little, m-Maybe I... maybe..."
But the more he talked, the worse it got. His voice cracked between the crying and the fear.
"W-Why did they leave me alone in a place this creepy?! What if a d-demon shows up from behind?! What if—?!"
"Good evening."
"IIIIIIEEEEEK!!!!"
The sudden voice behind him made every last hair on his body stand on end and he shot straight up like a spring, three meters into the air without thinking. When he landed, his legs gave out completely and he ended up on his knees against the ground.
'I KNEW IT!! I KNEW THIS WOULD HAPPEN!! I SAID IT!! I LITERALLY JUST SAID IT AND IT'S ALREADY HERE!!'
He covered his head with both hands and pressed his forehead to the ground.
"P-Please!! I don't taste good, I s-swear!! I'm nothing but bones and nerves, I'm not worth eating!! Eat the guy with the boar helmet, he's got more meat on him!!"
"..."
Marcus couldn't help but smile watching him like that.
He'd only meant to mess with him a little, but the reaction had gotten way out of hand. Before the panic completely took over Zenitsu—and especially before he fell asleep and things got complicated—he decided to speak up fast.
"Easy, easy. I was just messing around." He scratched the back of his neck, playing it off casually. "I heard you mention Tanjiro a moment ago. You know him, right?"
TANJIRO?!
At the sound of that name, Zenitsu's eyes—which had rolled back white from the scare—regained a flicker of life. Without leaving his dogeza, he raised his head, his neck stiff as a board.
And what he found was not a demon.
Standing under the moonlight was a handsome young man, dressed in a white haori and the Slayer Corps uniform. He wore two long swords crossed at his waist, and his green eyes had something kind about them... but also a mischievous glint he didn't bother hiding.
And the strangest thing of all: sitting on his shoulders, gripping his head with tiny hands, was a small girl watching him with her head tilted and a pair of enormous pink eyes full of curiosity.
"..."
Zenitsu blinked. Processed. And exploded.
"YOU YOU YOU YOU YOU!!"
The moment he recognized the Slayer Corps uniform and confirmed the guy was human, all his fear turned to rage in an instant.
"Do you mind explaining why you walk without making a sound?!" He jumped to his feet and jabbed a finger right in his face. "Who does that?! Huh?! Didn't anyone teach you that sneaking up behind someone in the middle of the night can SCARE THEM TO DEATH?!"
Marcus held back his laughter as best he could and put on his best innocent face. "Sorry, sorry~ I just heard you muttering my little brother Tanjiro's name and couldn't help coming over."
"Bro...? Little brother?!" Zenitsu froze for a second, then looked him up and down more carefully.
That face... something about it rang a bell…
It felt familiar, but he couldn't quite place it—until suddenly he slapped his own thigh hard.
"AH!! I know who you are!! You're the one who was with us at Final Selection!"
"Well, well..." Marcus's eyes lit up, genuinely surprised. "I thought you'd forgotten about me."
"Honestly, you didn't exactly leave much of an impression..." Zenitsu muttered under his breath, but the very next second he leaned forward with his eyes sparkling. "BUT!! There was a gorgeous girl with you back then! The one in the pink kimono with the black hair! She had this incredible presence! Who was she?! Where is she?!"
"..."
'It's Zenitsu, after all…'
"I'm Marcus." He introduced himself without fanfare and gave a few pats to the little feet dangling over his chest. "And this little one here is Nezuko, Tanjiro's sister."
Zenitsu looked up at the girl sitting on Marcus's shoulders. Nezuko blinked back at him.
Something crossed Zenitsu's expression, but he didn't say anything about it.
"...so she's the little sister Tanjiro's always talking about..."
It was obvious Tanjiro had told him why he'd joined the Slayer Corps. It was a complicated matter, hard to judge, and Zenitsu seemed to decide on his own that now wasn't the time to get into it.
Instead, he scratched his cheek. "Well, so... what are you guys doing around here?"
"A mission. You were sent to Mount Natagumo too, right?" Marcus glanced toward the mountain. "And Tanjiro? Did he already go in?"
At that, Zenitsu deflated like a balloon with the air let out and stared at the entrance to the mountain with watery eyes.
"Yeah... Tanjiro and Inosuke already went up." His voice trailed off. "...And they left me h-here. Alone. Abandoned…."
"Ohh… So they abandoned you?"
Hearing that mocking tone, Zenitsu whipped around with a vein throbbing on his forehead.
But what he found was worse than mockery.
Marcus was looking at him with an expression... hard to describe. A mix of compassion and pity, like he was looking at a wet puppy in a cardboard box.
And before Zenitsu could react, he put his hand on his head and gave him a few pats.
"There, there... Don't feel bad." He sighed. "I guess throuples always end up like this, huh? There's always one left out."
"..."
It took Zenitsu a second to understand what he was implying. And when it processed, his face turned red all the way to his ears.
"THAT'S NOT WHAT THIS IS, YOU PERVERT!!"
"Yeah, yeah, yeah, I get it~" Marcus pulled his hand back and waved it with total dismissal, wearing an expression that so clearly said "young people's relationships these days are so complicated" it could practically be read in the air.
Zenitsu stood there with his mouth hanging open and his finger raised, unable to get a single word out.
He felt that even if he died, reincarnated, and died again, he could never clear his name.
Above, Nezuko tilted her little head to the other side, understanding absolutely nothing.
Marcus looked up toward the entrance of the mountain.
It was pitch dark in there; barely enough moonlight crept in to trace the outline of a narrow trail disappearing into the trees.
"Since you're here…" He turned to Zenitsu. "Are you really planning to just sit here staring at the mountain all night?"
"..."
Zenitsu pressed his lips together and looked down, fighting with himself.
Of course he didn't want to stay alone in a place this creepy.
But in there... in there were demons! Real ones. The kind that rip your head off and eat it like it's a rice ball.
He opened his mouth wanting to say something, but the words wouldn't come out.
Seeing his struggle, Marcus sighed.
"All right." He put a hand on his shoulder. "Running into each other here is fate. I'll go in with you, deal?"
"Really?!" Zenitsu's eyes lit up like two lanterns. "You mean it?!"
He'd heard from Tanjiro that his Senpai was really strong!
No, not just strong—RIDICULOUSLY STRONG. If Marcus went with him, then... then he had a shield! That is, a reliable partner!
"Go."
Taking a step forward, Marcus headed toward the mountain trail.
And Zenitsu stuck right behind him immediately, practically stepping on his heels, though that didn't stop him from turning his head every three steps to check every shadow, every bush, every suspicious sound.
The path narrowed as they went deeper.
It was obvious nobody came through here often: the trunks and branches grew wild on both sides, unpruned, and some stretched halfway across the trail like twisted arms. Marcus dodged or pushed them aside without much trouble, but for Nezuko, still sitting on his shoulders, it was a different story.
At first she was fine. Calm, holding onto his head, looking at everything with curiosity. But then a branch brushed her hair.
"Mmh?"
She tilted her head and pushed the strand aside, not thinking much of it.
A few steps later, another branch nearly poked her in the face.
She scrunched her nose.
…Obviously, she hadn't liked that one bit.
They kept going and the trail got worse. The branches multiplied, lower, tighter, and they had to duck to get through them.
Nezuko took another branch to the face, and this time she let out a huff of protest and started patting Marcus insistently on the head.
"What's wrong?" Marcus looked up.
Nezuko pointed at the branches closing in around her like claws, then pointed at herself. Her eyes said it all without needing words: "I don't like this."
"Not comfortable up there, huh?"
"Mmh!" She nodded so hard her hair bounced.
"Well… then get down and walk on your own."
"..."
Nezuko thought about it for a second and with a "hop!" launched herself off his shoulders. When she landed she was still in her small form, her tiny feet touching the trail floor with a soft little sound.
But then she let out a "mmh," and her body began to grow. The pink kimono stretched with her, adjusting, and in the blink of an eye she was back to her original figure.
The moonlight bathed her face. Her pink eyes shimmered, crystalline, and there was something about her that seemed out of place on such a sinister path.
"..."
Zenitsu went completely speechless.
As if someone had unplugged his brain.
His face turned red in an instant, his heart started hammering against his ribs.
'She's... she's gorgeous…'
'She's the most beautiful thing I've ever seen in my life!!'
'Is this... is this what they call love at first sight? This tightness in my chest? This feeling like the world stops and she's the only thing that exists and—?'
A large, firm hand landed on his shoulder.
"Kid."
The voice reached him right in his ear, so cold it could have frozen the air around them.
Zenitsu felt his blood turn to ice before he even turned around.
Marcus was standing right behind him.
'When the hell did he move?!'
He hadn't heard him, hadn't felt him—he was like a shadow, and his smile... his smile was the least comforting thing in the world.
"Checking out the sister-in-law?"
Zenitsu's brain short-circuited.
'Si-Si-Si-Si-SISTER-IN-LAW?'
His eyes drifted to Nezuko again. He looked at her. Processed. Looked at her again. And made the mistake of letting Marcus catch him looking twice.
Marcus's smile widened. But his eyes... his eyes went completely dead, as if someone had blown out the candle of whatever warmth they'd had before. "...She's cute, isn't she?"
!
Zenitsu started trembling.
Not the trembling from before, the fear-of-demons kind. No. This was a new trembling, deeper: survival instinct screaming at him that the most dangerous predator on this mountain wasn't inside it—it was standing right behind him.
'He... help…'
'TANJIRO!!!'
'Your senpai is just like you said!! HE'S WORSE THAN A DEMON!!'
____
Welcome to the Mount Natagumo arc!🕷️
Zenitsu just found out the hard way that looking at Nezuko comes with a death wish when Marcus is around!
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