"There are no more spring rolls, dammit! You ate them all!" a servant with black hair barked.
"What the hell do you mean?!" a familiar brunette argued back.
"I don't even know why Im helping you, I don't even like you!!"
"You don't like me, then kill me right now!"
The black haired servant looked as if he were going to actually kill him, but he got dragged away by another maid to do different chores, stormy grey eyes following the whole time.
"Mordecai...?" Zenitsu asked as he peeked around the corner. The brunette grumpily whipped his head around, ready to rip anyone to shreds, but his glare softened when his gaze landed on his brother. "Mordecaaai!" the blonde celebrated and jumped on his brother, who fell to the ground. "Waah! Mordecai, it was horrible without you! I got bitten by an icky spider and then I nearly got turned to one!"
"Ew! Get off!" Mordecai snapped, though he failed to hide the fact that he was enjoying the hug.
"Eh? Welcome back Mordecai! What're you doing here?" Tanjiro greeted warmly.
"Lady Kocho found out that Zenitsu had a brother, so she found me and transferred me here since I was still healing. She truly is kind~!" Mordecai answered with a dreamy look on his face.
"Wow, okay lover boy" Y/n rolled his eyes and stuck his tongue out in disgust. He shot a quick, subtle side glance at Tanjiro before turning to the scene in front again.
Kanao walked past, quickly beaming at the group before continuing her way down the hallway. Tanjiro's eyes followed her. He looked deep in thought.
"Um... excuse me" a small girl tugged on his clothes. He didn't react.
"Tanjiro!" another one caught his attention.
"Oh! You scared me" the red headed boy breathed. "What can I help you with?" he asked.
"Um..." they shyly fiddled with their clothing. "Do you do total concentration breathing the whole day?"
"Hm?" Tanjiro hummed in confusion.
"What? Is that even possible?" Y/n piped up, interested in the conversation.
"Um, no, I dont believe we do..." Tanjiro answered, stroking his chin in thought. "Even while sleeping?"
"Yes. It makes a world of a difference to be able to"
"Using total concentration breathing even for a little bit is pretty hard... using it the entire day, is..." Tanjiro trailed off and looked at Y/n.
"...nearly impossible" the boy finished and furrowed his eyebrows.
"Some people are able to do it the whole day! Like all of the Hashira and Kanao. You two should try it!" the girls chimed.
"Thats a great idea. We'll try it!" Tanjiro thanked.
--
The duo tried over and over again for hours, but to no avail. They panted desperately for air, ears ringing and lungs aching. Tanjiro, out of fear of his brain leaking out of his ears, slammed his palms over them, scaring Y/n in the process.
The red head groaned, his head in his hands. "Agh! I suck!" he complained and let out an annoyed exclamation, making the e/c eyed boy jump again.
"I'm no better" Y/n sighed. "At least we suck together" he chuckled, earning himself a laugh from Tanjiro.
The 3 butterfly girls handed them a small platter filled with rice balls and gourds. A few minuted of silence passed.
"So you want us to blow into these gourds?" Tanjiro asked.
"Yes. When Shinobu was training Kanao she often made her blow into gourds such as these"
"Oh, interesting! Does it make a sound?" Tanjiro asked again.
"No, you're supposed to burst them!"
The duo paused. "We have to what?" Y/n asked after the few seconds of silence.
"Huh?! Burst these?! Dried gourds?!" Tanjiro exclaimed.
"Mhm! And these are special gourds, they're extra thick! And as training goes on, they get bigger! Kanao-san is working on this one!" they pointed at a huge gourd.
"Oh boy, that's big..." Y/n mused.
"But we have to try!" Tanjiro said determinedly.
--
15 days passed. The two were still trying to master total concentration breathing. They were currently on the roof of the butterfly mansion, meditating to expand their lung capacity. Even the normally fidgety Y/n seemed to be relaxed and still. His calm was broken when he heard Tanjiro emitting a frustrated sound. He opened his eyes and glanced at him, watching his normally calm face scrunch up into a frown.
"Hello" a voice rang, though it sounded far away. "Hello!" the voice said again, making Tanjiro's eyes snap open. The sudden movement made Y/n jump so far he nearly slid off the roof. He looked up to see Shinobu standing between them. "You two are really dedicated! Your friends ran off somewhere, aren't you lonely?" she asked and plopped herself between them.
"Nope, once we learn it we'll teach it to them" Tanjiro said with a kind smile.
"Hm... you have a pure heart" Shinobu hummed in delight.
"With all due respects... why did you bring us here?" Tanjiro asked carefully.
"Because I learned about Nezuko... and you two had terrible injuries. And... I thought I could entrust you with my dream"
"Dream?" the two young kids asked.
"Yes" Shinobu confirmed. "My dream of getting along with demons. I'm sure you two can achieve that"
Tanjiro took a sniff of air and Y/n listened out. Both looked at each other in confusion, since they both picked up anger from her. They had a silent conversation about whether they should ask about it or not. The red head eventually spoke up. "Are you angry?" he asked.
Shinobu's eyes widened a little in surprise.
"Yeah... you always sound and smell so angry. Why is that?" Y/n continued.
Kocho gazed forward, a little quiet. "Well, I guess you could say that... Ever since my beloved elder sister got killed by a demon, whenever I see a demon or those who've had their loved ones taken by demons... the anger in me only grows deeper. Deep inside me there's a burning hatred that simply cannot be tamed. It's the same for the other Hashira. Now that I've seen Nezuko, who hasn't eaten any humans, and sensed her true nature, I don't think any of them will harm her. Also because of masters will. My sister was a kind person like you. She felt sympathy for demons. Even as she died she pitied them. I couldn't think like that. Pity someone who kills other people? Thats crazy. But its what my sister wished for, and I must carry it out. If there is a way to kill pitiful demons... I will do it, without losing my smile which my sister had loved oh so much. But... its making me tired... Keep up your kindness, Tanjiro, Y/n. Please keep fighting for Nezuko. Thinking of you two fulfilling my dream" Shinobu thanked and stood up with a bow, before hopping off to do her own thing.
Tanjiro smiled after her. "We'll do our best..." he promised quietly.
--
"Naho, Kiyo! Sumi!" Y/n called out, running to the 3 butterfly girls from down the hallway.
"We want you to help us train!" Tanjiro asked. "The we're asleep, if we stop doing our total concentration breathing, hit us with these blanket beaters!"
The 3 girls stared blankly as they were handed the beaters. Their faces soon lit up. "You got it!" they exclaimed enthusiastically.
--
10 days of excessive training and less sleep than would be nice had passed. The duo blew into gourds every day, until they finally managed to shatter 2 large ones.
"We did it! Y/n, we did it!!" Tanjiro cheered and jumped up and down, embracing the said boy excitedly. He, in turn, turned a little red.
They then headed back to training. Kanao and Tanjiro were at it again, training as hard as ever. Y/n watched the red head train, his eyes following his every step. He watched in amusement as the red head ran around, trying desperately to tag Kanao. While he still didn't tag her, he was actually managing to keep up, which is improvement on its own. After a swift game of tag, the game of cups took place and Tanjiro was winning. Y/n could barely keep up with their quick movements. The boy playing the game grabbed the cup, but instead of actually pouring the tea on Kanao, he gently placed the cup on her head. Y/n stared at the scene, not sure what to make of it.
"Did... he just win?" he whispered.
"Placing in on her head is the same thing as pouring it on her!" one of the 3 butterfly girls confirmed.
Tanjiro soon came over to celebrate his victory with the group of 4, leaving Kanao alone and stumped.
Zenitsu and Inosuke sulked in the corner, and for good reason. Tanjiro had really tried teaching them how to do it, but they sucked at it tremendously. The group sat in a circle while Tanjiro did his best to explain. Y/n had already learned it, so he was barely paying attention.
"Tanjiro-kun, understand the skill of constant, full focus breaths" Shinobu piped up with her instructions and placed a hand on said males shoulder. "By continuing to do your full focus breaths all day and all night your base stamina will rapidly increase" she explained. "Well, I call it basic, but its really rudimentary, so its only reasonable that you can do it. However, to understand it, you need a considerable amount of effort" she turned to Inosuke. "Well, its only reasonable that you can do it. But if you cant I suppose there's nothing we can do about it. Nothing at all. Nothing" she chimed with a smile.
Inosuke looked furious. "Haah?! Of course I can do it!" he hollered at the top of his lungs. "Don't look down on meee! I'll rip your tits off, dammit!" he threatened, making Y/n choke on his tea.
"I'm sorry, what?" he asked, coughing a little bit.
Shinobu then turned to the blondie. "Please do your best, Zenitsu! I'll be cheering for you the most!" she promised, grabbing his hand. At this point, the poor boy was so red that his face was practically steaming. He nodded furiously. "And Y/n" she chirped and faced him.
"I know everything-"
"Shush" Kocho dismissed him. "Try to stay out of trouble, okay?" she chirped almost threateningly.
The next 9 days, the duo worked super hard and they eventually got it. Turns out Shinobu was an amazing teacher and Tanjiro extremely sucked at it.
"Inosuke! Y/n!" Tanjiro called out to the 2 and jogged into the training room. "They said our new nichirin blades are coming today!" he announced cheerfully.
"You serious?!" Inosuke asked excitedly.
"Yeah, I heard it from the crow!"
"Well what are we waiting for?! Lets go!" Y/n exclaimed with equal enthusiasm. The trio ran down the hallway, practically tripping over each other, before finally reaching the outdoors.
"Hey! Hey!" Tanjiro waved. "Haganezuka-saaaan! Its been a long time! How have you..." he trailed off when he noticed him running at him with a knife in hand. "...been...?"
"We should definitely run" Y/n piped up.
Instead of actually running, the two stepped out of the way, allowing the older man to run between them.
"H-Haganezuka...?!" Tanjiro asked in shock.
"How dare you break my blade?!" the masked man shrieked. "Damn you, damn you!!"
"We're sorry! I was actually gonna die! My opponent was super strong!" Tanjiro excused himself.
"Yeah, same for me! I was tied up and he broke it in front of my face!" Y/n did the same.
"Like that has anything to do with it!" Haganezuka snapped "Its your fault! Everything's your fault! The blade broke because you're weak! That must be why my blade broke! I'll kill youuuu!"
The old man ended up chasing them for hours on end. They eventually cooled down around the evening, each of them panting like mutts.
"Well, Haganezuka is a very passionate person. He loves blades more than anyone else. My name is Kanmori" another sword-maker introduced himself.