Somewhere far away...
Disclaimer: I do not own Kimetsu No Yaiba/Demon Slayer or any of its products, all rights go to Koyoharu Gotouge
Nezuko Kamado lifted her head from the intense pressure of her neck almost being chopped, and shook it off like it was nothing as a six eyed demon approached her, a stare of disgust reaching his face, at such a sight of a warrior with such potential. Before she knew it, the demon girl was gulping down blood from this mysterious person as her mind transformed, and spoke to Muzan, ''Lord, I will serve you.'' Her body yet her red eyes glowed in the snow, the demon taking over her, and following that, she said ''Master Kokushibo. Where do we start?''
Back to the mountains...
Tanjiro's legs burned as he sprinted through, ontop, below the traps, and a wood plank almost hit him in the cheek, and his bump mark on the right of his face had transformed, transformed into a mark that would activate every time he battles anyone, but this is not the horrendous mark from the greatest Demon Slayer, it was a normal mark that just lay on his forehead. In response, he caught it with his palm and used it to block the other oak shooting out at him, bursting and firing in rectangular slices that were thrown onto the floor and landed with a bang. He knew it wasn't over yet, until a shadow cast infront of him, and he muttered, ''A demon...''
Correct he was, and the demon mocked, ''Pathetic human, do you hope to slay me? Oh, you're such a joke! HAHAHAH-'' That laugh was interrupted by a slice cutting through his chest as he yelled in pain and muttered for it to heal as his face scrunched up in ruthlessness, saying ''You stubborn creature... go to hell.'' Blood Demon Art could not be released by the spiky-haired demon that stared at Tanjiro with an evil glare that stared beyond his body yet the boy released his emotions before he could, and judgement had struck. The demon was sliced off, but before it crumbled, it released the rest of its Blood Demon Art in him, and fists struck him on his stomach, face and right cheek, causing the apprentice of Urokodaki to cough out blood as a figure stood before him with hair that stretched just beyond his shoulders and a hideous mark that lay on his forehead, no emotion being expressed off him from his sense of smell as the figure said, '''I am Yoriichi Tsugikuni, and you are Sumiyoshi's descendant, correct?''
Tanjirou felt a sudden warmth overflow his heart as he bent down and bowed, ''Yes!''
''You're the person I'm looking for, one of my only friends had a descendant, and I'm guessing you've heard of Sun Breathing?''
'''Um, no, but I've heard of Dance of the Fire God and the creator was... YOU!'' Shock spread across his face as a humble laughter burst out of Yoriichi's mouth as he said,'' That's why I'm here, to teach you. You must call this Sun Breathing, as that is the real name. I'm sorry for any disturbances with that. Just breathe, and set your heart free, don't worry, as that's what needed to complete this Breathing..''
Tanjiro blazed back to the real world and realised why he saw that vision.. a horde of demons, mouths stained with blood, was approaching him, and he must use the family technique, for it is his only steel against the demons, and as his lungs expanded, a light fire lit from the blade as he wielded it with all his grip, soaring past the demons like they were flies as the figure of the greatest Demon Slayer crossed their minds with the Breathing as it was familiar to their Progenitor, Muzan Kibutsuji. His lungs almost shattered as his mouth vomited waves of blood staining the floor, a rock laying infront of him and he smiled at the sight. His blade sliced the rock and only a dent entered it, and a punch lifted against his gut, a boy around the age of twenty-one in a ghost like form and a girl around the same age laid next to him and they softly said, ''This rock isn't a piece of cake, they say only the ones worthy to pass the Final Selection of the Demon Slayer Corps, so you must work hard here unless you choose to give up?'' The boy shook his head and took the challenge, only hearing of the Corps in the myths and legends, yet it had become reality.
''Our names are Sabito and Makomo and we are here to help you cut the rock that lays here because you have not chosen to forfeit.''
The boy named Sabito readied his stance as Tanjirou did the same, the steel against wood making a creaking sword as a sharp pain striked the youth's face like a sharp whip hitting him a hundred times, and he staggered back, holding his cheek as he left himself wide open, soon recovering from the mistake as he tilted backwards, knocking his head against the wall as the lightly ginger haired boy told him, ''Tommorow, we'll continue this.''
A year passed..
The boy, who came in weak and skinny with cut hair, had long hair that stretched down below his shoulders and made him look like his master, who was watching him progress. Sabito striked for his face, again, yet the boy dodged and sliced his mask, and before he knew it, he was smiling at him and disappearing and a hug enveloped the dissolving boy as tears streaked down his face, thanking, ''Thank you, thank you, thank you, thank you so much! Farewell...''
''Farewell... Tanjiro Kamado.''
Tanjiro walked down the mountain faster than he came up with the training he had recieved and he jumped from a tree and landed infront of Urokodaki, and he said, ''My student! You've done it... now go to the Final Selection and join the Demon Slaying Corps, wait before that, let me show you something!'' Urokodaki took the katana and breathed in and out, clearly demonstrating something as water enveloped the sword...