-3rd POV-
"Get lost, will you?! I'm not giving you that key, no matter what! And don't think I'm ever going to show you how to use it!" The kid argued with Muichiro.
'What's going on? Are those two fighting, maybe?' Tanjiro thought, watching, 'What should I do? It's bad manners to eavesdrop! But if they're fighting, I should try to mediate...' Then his eyes widen.
Muchiro had slapped the kids face, making him fall, shocking the burgundy haired male and (Y/n). He then picked the kid by his collar.
"Cut it out!" He exclaimed, running up, and grabbing the Hashira's wrist, "What do you think you're doing?! Take your hands off him!"
The white haired girl facepalmed, 'Now, I have to help Tanji-chan...' She thought.
"Your voice is very annoying. Who are you?" Muichiro questioned him.
"How could you do that to a little kid? Take your hands–" He cut himself off as he looked down at his hand, 'He's not even budging! He's got thinner arms than me, and he's not very big!'
"You take your hands off me." He said, as he then suddenly elbows the male's stomach.
Tanjiro fell to the ground.
"You're quite weak." He said, watching the male cough, "It's a wonder you got into the Demon Slayer Corps." He then noticed something, "Huh? I'm getting a strange vibe from that box. A demon's presence, perhaps?" He stared at Nezuko's box, "What's inside? That box there?" He reached for it, but his hand was slapped.
The burgundy haired male glared at him, "Don't you dare touch it!"
The Hashira looks at his hand that was slapped, then looked at the red coat he held of the kid, seeing that he was no longer in his hand. He looked at the (Y/n), 'She took him.' He thought, staring at her box, 'She has a demon? No...there's several.'
"Are you all right?" The girl questioned the kid.
"L-Let go of me!" The masked kid exclaimed, pushing her away.
"You must be dizzy. That's dangerous!" Tanjiro exclaimed.
"Get out of here!" He then turned away from the two slayers, "I'm not...I'm not giving that key to anyone! Not even if you torture me! No way! One more time, and it's going to break down!" He said, looking at the machine.
Muichiro walked up, "Have you been through torture training?" He said, making the three turn to him, "Even most grown-ups can't take it. You'd never last. I can see that you're stupid beyond belief. So what if it breaks down? Just make another one. How many people do you think will perish while you drone on and on about trivial matters?"
The three let out small breaths as they listened to his words.
"That's what it means to obstruct a Hashira in his duty. A Hashira's time is worth far more than time spent by you people. If you think a little, you'll eventually get that, won't you? Swordsmiths can't fight. You can't save lives. Making weapons is all you're good for."
The kid had tears threatening to come down the mask, as Tanjiro and the girl frowned next to him.
"Come on. The key." Muichiro outstretched his hand, "Remember your place whenever you take action. Since you're not a baby anymore."
The burgundy haired male and the female slapped his palm.
The kid was shocked by their actions.
"What are you doing?" He questioned the two.
"I just..." Tanjiro shook, "I don't know why, but...I can't stand you! What is it? Tact, maybe? You have no tact, and you're cruel!" He exclaimed, wiggling his fingers.
"Cruel! Cruel!" (Y/n) raised her fist.
"You think this is cruel? You..." Muichiro trailed off.
"You're not wrong! I admit that what you're saying is mostly true, and it's probably not wrong! But being a swordsmith...is an important, vital job!" She exclaimed.
Without their knowledge, someone stood behind the tree, listening to their conversation. Which was Haganezuka.
"Swordsmiths have amazing skills that are totally different from ours! The fact is that if we didn't have them to forge our swords, we couldn't do anything, could we?" She said, as the Hashira looked down.
"Swordsmen and swordsmiths need each other! We're all fighting the same battle! Day in and day out, each in our own way, we're fighting–" Tanjiro was cut off.
"Sorry...but I don't have time to stand here listening to your boring speech." Muichiro said, looking at the two, before striking the male, making him fall and go unconscious. He then looked at the girl.
"Now, now. Mui-chan, no need to be mean." She smiled.
He blinked at her, "Do I know you?"
"Nope." She grinned.
He stared at her, before the kid ran up and threw the key at him, to make him leave. He stared at the key, then left with the mech.
She looked at the kid, "Pretty brave of you." She said.
He looked down, "I didn't want you to get hurt too..." He trailed off.
She smiled and pat his head, "It's okay. So, what's your name, kid?"
He stared at her, "Kotetsu..."
"Kotetsu...Ko-chan!" She grinned.
"Wha?! It's Kotetsu! Not "Ko-chan"!" He exclaimed.
She ignored his words and looked at unconscious male, gently poking him with a stick she found.
"What should I do? Can I carry him down by myself?"
"No. I'll carry him. As long as he doesn't come to soon." Haganezuka walked up, making the girl grin. But he noticed the teen slightly twitch, "Huh? His eyelids are twitching! He's about to wake up! See you!" He ran off, shocking the two.
"Huh? Hey!" Kotetsu exclaimed.
"Come back!" (Y/n) called out.
Tanjiro instantly opened his eyes and sat up with dotted eyes.
"Uh...Are you okay? You shouldn't get up so fast." The kid said.
He turned to the two, "Was Mr. Haganezuka here?"
"Huh?" He was startled.
"Wasn't he here just now?"
"No, he wasn't here!" He looked away, making a sound.
The burgundy haired male looked at the girl, "Did you see him?"
(Y/n) grinned and shook her head, "Nope. You must be hearing things." She said.
"I see. So I was just imagining things." He then turned to them, "Ah...Where's that Hashira?"
"I handed over the key, so he took off." Kotetsu said.
"So you handed it over, huh? I know you didn't seem to have a choice. Well, since I don't know what's going on, I shouldn't be making a fuss about it." He rubbed his neck, where he was hit.
"Oh no, don't say that! It made me happy. I'm a stranger to you two, but you both stood up for me. Thank you very much!" He bowed to the two.
"No, I wasn't that much help!"
The girl smiled, "I wasn't any help either, Ko-chan." She said, as the two bowed.
"Where's that man or whatever who was standing here?" Tanjiro said, looking at the opened box.
"That was a mechanical doll." The kid said.
"Mechanical doll?"
"That guy just took it away with him. He needed the key to make the doll move." He gripped his pants.
"So it's really important to you, huh?" The girl questioned, as he nodded.
"But what would a Hashira want with it?" The burgundy haired male said.
"That one's special. That mechanical doll can overpower a human, and it's capable of 108 moves. It can be used to train for combat."
"So that's why..."
"But...now it's..." His voice shook.
Though, they all heard the sound of a sword strike through the area, shocking the three.
"What was that?" The white haired girl said.
"That guy must've already..." Kotetsu trailed off, before getting up and running, "This way!"
The two follow after him.
-----
Muichiro runs up to the doll, jumps as the doll, swings one of the blades, then one of the blades tries to hit him, but he dodges by twisting himself.
The doll raised an arm and swung down, making the hashira drop low to the ground and swing his blade, clashing with one another. The doll then swung again, but was only dodged by the male jumping back.
By the woods, the two slayers and Kotetsu watched.
"Against a Hashira...Wow!" Tanjiro said, shocked.
"That's the mechanical doll built by my ancestors. Yoriichi Type Zero." The kid said, as he watched the doll.
"But..." (Y/n) turned to him, "why does he have six arms?"
"His arms?" He turned to her, then back at the fight, "According to my father, that doll was modeled on an actually swordsman, but his moves couldn't be replicated unless they gave it six arms."
She let out a soff hum.
'That face...It somehow seems familiar, but I'm not sure.' Tanjiro thought, then turned to Kotetsu, "That swordsman...Who was he? What did he do and where?"
"Uh, sorry, but I don't know too much about him, either. Since he was from the Sengoku Period." He said, shocking the two.
His eyes widen, "S-Sengoku? You mean he lived more than 300 years ago?"
"That's what I was told."
He looked at the doll, "It's never broken down in all that time? That doll?"
"The technology's so mind-blowing, we can't catch up to it today. If it were to break down, there'd be no fixing it." He said, making the two turn to him, "My father passed away suddenly, and I have no brothers or sisters. I'm the one who's supposed to step up now, but since I'm no good with swords or mechanical dolls..."
"So that's why you were so..." Tanjiro trailed off, "Right, I get it." He looked at Muichiro, "That guy's incredible. He's only around our age...but he's a Hashira, and he's so talented."
"Well, what did you expect?" A voice said, startling the three.
"After all, he's a descendant of the wielder of the Sun Breathing technique!" They looked at the crow behind them that had long eyelashes, "That boy is a prodigy! He's in a different league than the likes of you!" The crow laughed.
(Y/n)'s brow twitched, "How about I cook you, hah?" She grinned, making it panic.
"You're an exception Gojo-sama!"
She had a flowery aura, "Good."
Tanjiro sweatdropped at the girl, then looked at the girl, "Are you Tokito's crow? The first breathing style, Sun Breathing?" He turned to look back at the said male, "So he's really that amazing."
Muichiro dodged another attack.
"But that's not Sun Breathing that he's using now, is it?"
"Huh?" The crow's eyes widen, before biting the teen's cheek, making him yell out in pain, "You shut your mouth, or I'll gouge out your eyes!"
His eyes then widen, "Hey, I remember now! That dream! I saw that man in a dream!"
"Huh? Are you an idiot or what? Have you been to this village before? That's so preposterous, you make me laugh! You mean you've met a warrior from the Sengoku Period? How old are you, exactly? Huh!"
The male only grumbled with dotted eyes, "Listen, I'm sorry. There's something wrong with me, right?"
"No, no!" Kotetsu and (Y/n) waved their hands.
"Maybe it's an inherited memory? People talk about it all the time in our village. It isn't just your physical form that gets passed on. Living creatures pass on their memories, too."
The burgundy haired male's eyes widen.
"What you saw in your dream must've been your ancestor's memory!"
"Preposterous! Preposterous!" The crow exclaimed.
(Y/n) grabbed the crow, "If you don't shut up, I'll cook you and give you to my demon friends." She looked at her box, "Doesn't it sound nice, guys?"
"An annoying pest like that? Don't make me laugh." Sukuna said.
"Onii-chan and I don't want it." Daki said.
"No thanks." Akaza said.
"Ah, I guess they don't want you, more for me I guess." The female slayer grinned, making it panic.
"That's so kind of you! Thanks!" Tanjiro smiled, "I'm Tanjiro. What's your name?"
"I'm Kotetsu. Don't pay any attention to that mean female crow. I'm sure (Y/n) will cook it soon." He said, which shocked the two and made the girl laugh.
Though, they then turned their heads when they heard the sound of the doll being hit.
"Huh?" Kotetsu said, watching some of the pieces fly off.
"Hey! His armor!" Tanjiro exclaimed.
His teeth clenched behind the mask, before he turned and ran off.
"Ko-chan!" (Y/n) called out.
-----
"Kotetsu! Kotetsu! I'm going to find you! I've got a great sense of smell! Even if it's not in good shape right now." Tanjiro said, walking in a direction as (Y/n) followed, "I think he went this way..." He sniffed the air, then looked up to see the said kid on the tree.
"Ko-chan! Could you have climbed any higher, Ko-chan?" The girl said.
"If there's anything we can do, we'll help you out. You can't give up on your doll! You have a future ahead of you!"
"Huh?" Kotetsu said.
"You have to try hard now for your future self...ten, twenty years from now! Someday, you'll be able to do what you can't do now!"
"No, I won't! I don't need anyone to tell me that I'm a loser!" He wiped the side of his face, tears dropping, "It's all going to end with my generation! All because of me!" His voice cracked, then turned his head, "Huh?" He saw the two slayers on the tree with him.
"Huh?" Tanjiro said, before flicking his chin.
"Ouch!" Kotetsu winced.
"You can't give up and stop caring. I wish you wouldn't talk about yourself that way." (Y/n) said, patting his head, "Trust me. I thought the same way."
'They came without making a sound. That's what a swordsman or swordswoman can do.' The kid thought.
"Even if you can't do it yourself, there's always someone who will carry on for you. You have to do what you can so that it gets passed on. Even if it's beyond you, maybe your kids or grandkids might find a way, right?" Tanjiro said, making the kid let out a small gasp.
"I want to defeat Kibutsuji Muzan. I want to save my sister, who's been turned into a demon. But I might die before I can fulfill my goals. But I have faith that someone will surely finish the job for me. Just like we were able to beat an Upper Rank demon with the lives that were connected for us, someday, for sure, the lives we've connected will bring down Kibutsuji!"
(Y/n) smiled, "I want to kill my old man. Well, my whole clan for that matter, but that's besides the point. I've been viewed my whole life as a goddess with unnatural powers to the point that I've been shunned. I got pretty lonely, so what did I do? I left, kidnapped Suku-chan, met Tanji-chan and Nezuko-chan, made new friends. And with everything that I have done so far...I'd say I've come a long way. I know someone in the future will continue my legacy."
The two grabbed the kid's hands, "Let's do our best together!" The two said.
Kotetsu let tears stream down as he nodded, "Okay. I didn't want to see the doll break down, but my mind is made up now. The combat training should last until nightfall, so I'm going to brace myself to see it through. To the end."
The two slayers grinned brightly.
-----
"Really? So you're ten, Kotetsu?" Tanjiro said.
"Yeah." Kotetsu nodded.
"My little brother is–" He cut himself off, when they saw Muichiro walk past them.
"Huh?" The three said.
"What? You're done?" (Y/n) questioned.
"I'm done. That was a good training session." Muichiro turned to them, "Who are you again? Oh, right. My sword snapped, so..." He raised his hand, shocking the three.
It was a sword from the doll, arm still attached to the handle.
"I'll be taking this one with me."
Kotetsu was shocked, fingers twitching, as he then ran off to find the doll
"Kotetsu–/Ko-chan!"
The Hashira threw his sword and sheath at Tanjiro's head.
"Ow!" He exclaimed.
"Dispose of that one for me." Muichiro said, turning and leaving.
The teen rubbed his head, 'Not a whiff of malice. He must not be doing that on purpose. But the thing is...'
They watched the crow land on the Hashira's shoulder, turning their head at them.
"Humph!" It huffed.
(Y/n)'s brow twitched, 'I'm using flame breathing on your crow ass! Try me!' She thought.
'That crow is just oozing spite. She's so condescending...toward me.' The burgundy haired male thought, before gasping and turning, "Kotetsu!"
-----
Rain began to fall as the two slayers ran back to where Muichiro was training.
They paused, seeing Kotetsu standing near the broken doll.
"Kotetsu..." Tanjiro walked up, "Let's make sure. Let's see if it still works or not." He said, making him turn to him, and nodded.
Soon, he held up the doll up. The kid pulled back it's shirt to reveal its back and wind the key. Then, they stood in front of it, seeing that it didn't move.
"Nothing. So it must be..." Kotetsu trailed off.
Though, the doll whirred to life, shocking the three, as it then readied itself for a fight.
"All right! It's working, Kotetsu! That's great–" Tanjiro cheered, before looking at the kid.
"Yes, it is, Tanjiro." He looked down, "I want you to train with this doll and become stronger than that indifferent little jerk, no matter what! And you will have my full support!" He angrily said, turning to him, veins protruding.
'Huh? Does he mean right now?' He thought, shocked by his words.
The doll looked up, then lurched forward, making the male let out a yell.
-----
The doll tried to hit Tanjiro with the wooden clubs, but he barely dodged and fell. The teen's eyes widen as he saw the doll stab the clubs into the ground as the male rolled away with a yell.
"I'm gonna die! Six arms is too much!" He exclaimed.
"There are only five arms! Since that jerk broke one off, it's less functional now!" Kotetsu said, watching the male stand, "Tanjiro, please become stronger! And this is what you're going to say to him..."Is that all you've got, you scumbag?""
He turned to him shocked, "Huh?"
""Your hair is too long! Get a haircut, seaweed head!" "Pissant! You're ugly, and your legs are short!" "Commit harakiri!" "You shameless jerk!"" He said, as (Y/n) laughed in the background.
"No! Kotetsu! That's going a little too far!" Tanjiro exclaimed.
He tilted his head, "Better to put his head on public display, you think?"
"No! I can't say those kinds of things!"
"You're going to say them!"
"No!" He turned from him.
"Please say them! Please!" He said, tugging his cheek.
The girl raised her hand, "I'll definitely say them!" She exclaimed with a grin.
Though, they all turned to the doll, seeing it run towards the male slayer and swung, making him dodge.
'Even without my saying so...Tokito was incredible! Despite being smaller and the same age as than me. I've got to train just as hard! I've got to become stronger, too!' Tanjiro thought.
The doll swung and he blocked it. It swung again, making him dodge, before he was hit in the stomach, making him fly back and fall to the ground.
He rolled to the side, holding his stomach.
Kotetsu ran up, "Tanjiro! If that's enough to kill you, you're pathetic! Keep working at it! I'm going to say it one more time! Look at me!" He said, repeatedly hitting him on his back.
The said male twitched slightly as he then got on his knees.
"You're moving out of habit, Tanjiro, all right?" He said, making his eyes widen, "You're not deciding how to move after observing your opponent's moves. That's why you're no good! Do you understand?"
Tanjiro could only stay silent, tears pooling and sweat dripping.
'Imagine being called out by a kid...' (Y/n) thought, grinning.
"In other words, you don't have the basics down! I'm really amazed you've managed to survive this long in the Demon Slayer Corps! You're cutting it close with everything you do! Well, I'm here to denounce your every weak point backward and forward! I'm not giving you any food until you can do everything I tell you to!" The kid exclaimed.
The burgundy haired male let out a small noise, "Right." He said.
-----
Tanjiro was struck by the doll, making him grunt and his head was dragged on the ground, leaving a trail.
"Tanjiro, you're too slow! Epic fail! If that doll wasn't armed with practice sticks, you'd be dead! Get a hold of yourself!" Kotetsu said.
The said male slowly got up.
"This is day five! Starting tomorrow, I'm going to arm the doll with swords!"
"No, even the practice sticks could kill me! I'm going to die!" He said.
He walked up, "No food for you today, either!"
He looked up at him with tears.
Ah! The highly analytical Kotetsu!
"Come on, get up! Get on your feet, please!" Kotetsu said, tugging the male's uniform.
But as a swordsmanship instructor, he was a total amateur.
"Hold on a second! Just a second!" The burgundy haired male said.
"Come on!"
Since he had no idea about the limits of a human life, his training sessions were brutal! So tyrannical...he'd withhold food and water from you if you failed to meet his demands!
Tanjiro stood in front slowly walked up to the doll, cheeks sunken in.
After three days or so without water, a human will seriously die.
He turned to him, who had his fists up.
Unclouded Gaze!
Pure tyranny born out of ignorance! Though I was able to survive, thanks to some rainfall.
Tanjiro screamed as he stuck out his tongue, catching the water from the rain.
-----
All through these ghastly training sessions...
The doll had swords now and swung the blades as Tanjiro dodged.
I went without water...without food...without sleep.
As he ran up, he lost consciousness.
I started to cross the River to the Afterlife. I was walking across a bridge, feeling indescribably blissful...only to get dizzy from hunger...and fall into the river.
Tanjiro's spirit fell into the river, making a splash as other spirits looked.
It was dark in the water...and heavy...but then it felt as though...I were being massaged by some warm hands.
As his spirit went deeper and deeper into the water, hands appeared and touched his body.
I saw something shiny when I glanced toward the bottom of the river..so when I went to get it, all while being massaged. Strangely enough...I could smell this shimmering stone even underwater.
He grabbed the stone and suddenly he's back awake.
'What is this? This smell? It smells different from than the opening thread.' He thought, as everything moved slow for him, seeing the doll swing, 'Left side of the head!' Looked up, 'Neck!' Then at the other arm that was up, 'Right side of the chest!' Then down, 'Left side! Right thigh! Right shoulder!' His eyes widen, 'Here it comes!'
The doll swings and Tanjiro barely dodges the attack, as he turns, then swings at the doll's legs, falling to the ground.
"You got one strike in, Tanjiro! Though it was so feeble, the doll didn't even flinch! I'm going to give you some food!" Kotetsu said.
'The doll isn't even alive...' (Y/n) thought, sweatdropping.
The male instantly looked at him, tears streaming down, "Rice balls and pickled plums! And I want high-quality gyokuro tea!"
-----
"Tasty!" Tanjiro cried out, eating the onigiri with both hands.
-----
Tanjiro dodged the attack, the blade cutting some of his hair, ran up as he dodged more of the attacks.
'All right! All right! I see how he's going to move!' He thought, blocking one of the blades, then dodged another, 'I can see it way better than before! I can keep up now that I have my stamina back!' He dodged again, as it then spun, making him jump back, 'Now, I can tell by the scent where he's going to strike!'
He run up to the doll, 'I can pick up this scent...sooner than I can see the opening thread!' He dodges the attack by jumping over it, 'All right! I'm going for it! One strike with all my might!' Then his eyes widen, 'Hey...But what if it breaks?' He twisted the blade.
"Strike!" Kotetsu exclaimed, shocking the slayers, "I don't care if it breaks! I'll fix it, no matter what!"
The burgundy haired male gasped, before having a determined look.
'Tanjiro, you're too nice! You can't hesitate now! But that's who you are, Tanjiro...and I don't want you to die!' He thought.
The doll cuts off a bit of the male's hair.
'I want you...to become stronger than anyone else!'
Tanjiro spun, blocking the blade and snapping his borrowed blade in the process. He then fell on his behind, "Ouch!" He exclaimed.
"Tanji-chan! Are you okay?" (Y/n) called out, as the two ran up to the injured male that held on to his behind.
"Ow, ow, ow...S-Sorry...I broke the sword you lent me." He said.
"Don't worry about that! It's okay!" The kid said.
The doll's neck shatters, and its head begins to fall
"Huh?" He turned to the doll.
"Hey!" The three exclaimed, before they see something sticking out from it, making them hug each other.
"Something came out! K-Kotetsu! Something came out! What is that thing?" Tanjiro exclaimed.
"Hey, hey! I have no idea, either!" The kid said.
"We're gonna die!" (Y/n) exclaimed.
The face of it fell, before it fell to it's knees.
"What could that be? At the very least...it's a sword from over 300 years ago, right?" Kotetsu said, as the two stared at the sword that peeked out from the doll.