Many slayers Gathered in the Training hall, on reflex training, Tag and stretching. Tanjiro and Muichiro with a Pair of 5 year old twins standing Infront of the other slayers, A boy looking like Giyu, with a blue kimono, black hakama pants, a Dark blue Raven Haori, short raven hair, and black socks, and a Girl looking like Kanae, long hair, 2 crow wing hairclips on each side, a black dress with a blue ribbon on her dress's hip, Black socks(caterpillar trio uniform but black), A dark blue Raven Haori and both twins ocean blue eyes. "Since this is a recovery training for ranks in between Tsuchinoe and Tsuchinoto. This training won't be simple until you get used to it. 1st off, Prevent your opponent from splashing medicine at you as of Reflex training, 2ndly stretching, is as simple as it'll help your bones be at good shape and lastly, Playing Tag." Says the boy name Tomioka Giichi, The Caterpillar Trio helping in stretching, them up, and Tanjiro and Muichiro with Tag and Cup holding reflexes. As for the Tomioka Twins, Giichi and Yumi, the children of water and flower Pillar, assisting by helping them with push-ups while having 3 heavy baskets on their backs.

As 3 weeks passes on, 'many slayers ended up exhausted and losing quite often. While Tanjiro helps them to breath properly, Muichiro insisted in there sword reflexes. According to them, it's like receiving training from a pillar because they are far from being Tsuchinoe, their strength is way above that. Either way, they slowly got used to it, and slowly got back to their fighting shape. Since it is said that the population of demons increased, Man power and Harsh training is required, therefore we must have them to stay sharp. While Tanjiro and Muichiro are on another level.' stated Giyu who he has been watching over the training and seeing how well it's going until now.'

Hours later, As Both Tanjiro and Muichiro on the yard with their wooden swords. Some slayers ended up witnessing since they are ordered to take fresh sunlight to recover fast, And as for the ones watching from the inside the living room, Giyu, Kanae, Shinobu and Shinobu's tsugoku, Himari Yuki, who she seems around Tanjiro's age, High pony Tail with an ice blue butterfly ornament. Sitting next to Shinobu whom she just arrived after a long term mission. "So, what did i miss Shinobu-sensei?" "Nothing much." Says Shinobu

As both Tanjiro and Muichiro getting ready "ready for the burn?" Asked Tanjiro "Depends." started sparring like crazy as it's been lasting for 20 minutes, many others stunned by how these 2 are sparing with mysterious breathing techniques. "Moon breathing, 3rd form. Dark night, Moonlight haze" Muichiro dashing around Tanjiro while he manages to block every attack, but Muichiro is constantly charging to him 'so this breathing technique is his own modified version of it, well done, looks like this form lacks Defense. Which means' thought Tanjiro as he performs "Hinokami Kagura: Burning bones, summer sun." he spirals his body and slashed everywhere and managed to defend himself from Muichiro's attack, he dashed to Tanjiro as begins slashing at him, Tanjiro blocking his attacks while going into a dancing position "Hinokami Kagura, Raging Sun." slashing 2 times at the same time Muichiro on his move "Moon breathing, 2nd form: Pearl Flower, moon Gazing" slashing Three times as Tanjiro blocks first and second slash but the third slash coming in as he immediately "Dance!" Slashing Upwards vertically in an arcing motion. As Both wooden swords clashed at the same time. As both has gotten, and Muichiro seemed surprised as he said "combining forms is quite common, and creative." "And your version of moon breathing quite amazing." Says Tanjiro as they both continues Fighting and meanwhile the pillars are watching this with Shinobu watching "Ara ara, that's quite the duel, what kind of breathing techniques is this, never heard of Moon nor this..." Says Shinobu as The voice of Tanjiro's crow who's sitting with the Pillars and a tsugoku "mahahahaha, Sun breathing, Tanjiro is wielding Sun Breathing, the 1st breathing technique where all others Derived from." Says the crow and they seemed surprised as Yuki says "hehhh? Sun breathing? 1st breathing technique? I never heard of it." "That's because it was long but forgotten as it has been passed down to Tanjiro's family for generations, the breathing technique, the sword and knowledge of all from the sengoku era. I call him, 'the child of fire god' since his sword is always on fire." Says Matsuemon which Giyu watching the kids sparring "it's true, I've seen him in action, and he's already like Pillar level. And he is already a full fledged Swordsmen when i found him." Says Giyu "Giyu-kun, you think they'll be a Pillar soon enough?" Askes Kanae replied "in a sense, Yes, i could see how strong they both are in equal footing." Both Tanjiro and Muichiro ends up shattering eachother's wooden swords, resulting in a tie as Muichiro says "you are quite strong." "And you are very talented." Says Tanjiro. "Shall we try again while.." Tanjiro Jumps to the fence, standing on it as he grabs another wooden sword. "We are stand at this?" Muichiro points his hand to a stack of wooden swords as his Crow flies down, grabs a wooden sword, throwing at Muichiro as he catches it. He hopped on the fence as they both started sparring while going around the fence. Giyu seemed surprised as they are quite confident to continue fighting and sparring while around the fence.

3 days Later, Tanjiro in the infirmary, as he received a Letter from Matsuemon delivering it. "Read it Tanjiro!" Tanjiro reads it as he was surprised

"Kamado Tanjiro

I'm well looking forward to meeting you, You and Muichiro are something I can't express how much im thrilled to hear more about you. Your sister saving herself from being a demon, You have Sun breathing, and the sword of the first breath user for generations you brought not only Sun breathing back, but also Moon breathing back into our generations, and lastly you crossed paths with Kibutsuji Muzan, you managed to Shook him into the core, as a result the population of demons are slowly increasing. I could believe that you are the key in helping us defeat Kibutsuji, you are one promising child to think that and I have high hopes for it. Stay strong, The incident at Asakusa was just the beginning. And Send Lady Tamayo my deepest regards until then, i wish you luck.

Yours truly, Ubayushiki Kagaya."

As moments passed in the Headquarters, where Kagaya received the letter, "a letter has arrived Father. It's from Kamado Tanjiro." Says the kid with black hair, Ubayushiki Kiriya. "Read it for me my son."

"Master Ubayushiki,

I give you my thanks for accepting me in, and since you addressed me as some final hope, i would advise you to try not to get any hopes up and assume it'll be easy since it's clearly not. For you to understand, Being a Sun breath user, doesn't make anyone automatically the most powerful within seconds. It takes a lot of training to reach it's potential. And It took years for my family to earn such a strength, by manifesting the demon slayer mark and I'm close to earning it. It's been running through my family since the first breath user, Tsugiikuni Yoriichi, passed down his strengths to us. And each of my ancestors died at the age of 35 from the mark, my Father, my grandfather and so on. Even my father was powerful as a pillar through light speed. Not even an unmarked pillar would be able to tell what happened. And as for Kibutsuji, he is probably increasing the population because when he saw me, he looked like he's seen a ghost. I figured he Saw Yoriichi in me from my earnings and his sword which I'm wielding. Regardless, I'm very much Training hard to be as strong as i can be. And Since I'm close to manifesting the demon slayer mark, I'm sure it will help the others out. My family and I pray for your family's health in good condition. Until then, I look forward to meeting you too someday.

Yours truly, Kamado Tanjiro."

Later on at Night, as Tanjiro is on the roof, meditating as he breaths and doing his best to keep it in control, closing his eyes 'this will help me with my health since I'm in the need to manifest the mark, my body temperature has reached 39 Celsius, my Heart rate is what remains'. As he starts clenching his teeth, breathing harder as fire is coming out of his mouth in between, "Moshi mosh." 'harder, 200 times the force.' thought Tanjiro as he breaths harder from fire coming out "Moshi mosh!" Tanjiro opening his eyes as he saw Kanae sitting next to him "ara ara, you seem to be working harder. Are you... feeling alone here?" "No, it's quite nice here." Says Tanjiro as Kanae says "you have such a precious heart." Tanjiro ended up seeing his mother in her as he faces away slowly to the sky "say, why did Master Ubayushiki send me here to stay? Unlike any other slayers unless they are wounded." Asks Tanjiro as Kanae replied "you need a place to stay, do you not? Infact, I'd like to share a little dream." "Dream?" Asked Tanjiro as Kanae smiles and replied "yes, About Demons getting along with humans, it would help us out." Tanjiro faces to her as he smells something "Are you Sad?" Kanae's smile vanished in shock "i always picked up a scent of sadness at random times from you, even when You're always joyful." Kanae faces down as she says "maybe you are right, maybe I'm always sad...My sister Shinobu lost 2 of her Tsugokus. Himari Yuki is her Third, Giyu-kun lost his sister to a Demon, I for one almost died from an upper moon, when i bumped into one. Giyu-kun was shattered when he watched his sister getting Absorbed, Flashback of young Giyu screaming "NEEE-SAAAAANNNN!!" With tears coming out, while others tried comforting him. Another Flashback plays with Shinobu Crying while Holding her 2 Tsugokus in her arms "No no no nooooooo! Akaaaaariiii! Tomoeeeee!!" Flashback ends with Kanae tearing out as she says "watching others in pain out of loss, and it hurts me the most...And I'm tired...i just want this to end. You said it before, that Kibutsuji fears Sun Breathing, right? Since your the only one left. Then i hope you can help us..I believe in you, Kamado Tanjiro. The master has high hopes for you, stay strong." "I will, and i won't let you and the Ubayushiki Family down. I will do my best." Says Tanjiro as Kanae smiles as she says "Thank you, you are such a pure hearted boy." As she vanished. Tanjiro faces to the moon with him in his thoughts 'Yoriichi-san, I promise. I will not fail.'

As 5 weeks have passed which Tanjiro and

Muichiro doing 1000 Pushups with the Giyu and Kanae on top of them, as such doing a 1000 times more. Tanjiro's thoughts 'every day, we both train harder with the Pillar of water and flower assisting us...' Both running while carrying heavy baskets "Train until your bones shatter!" Yelled Giyu as both are on it '..Tomioka-san does seem harsh when it comes to training, it is something which is bound to happen when reaching pillar strength..' Muichiro and Tanjiro going in Separate ways for missions 'We recieve missions by our Kasugai Crows, as such we intend to receive company by other slayers. Until then, Muichiro and i are now at higher kill count. To think that the population of demons increased. Every mission was around dealing with 7 or 9 demons. To the point that we get to have 14 slayers, Either or way, Muichiro and I tend to go separate missions when we are at it. Many people are stunned by my blade being on crimson fire and Muichiro's breathing technique is scaring almost alot of slayers, we protect alot of them and as such, they are doing a good job but most of the weak points of every slayer remains. I may have some plans for that.'

Almost 2 months passed since Tanjiro, Yuki and Muichiro in a Butterfly mansion, training with Giyu, Kanae and Shinobu. "Caw! Tanjiro, Muichiro, Yuki, make your way to an abandoned Village. They are a couple of demons there, make your way there as i will Guide you." Says Matsuemon. As Tanjiro, Muichiro and Yuki on their way to their Destination running as fast as they can. "safe journeys! yelled Aoi and the Caterpillar trio

Taisho Era Secret: The Children of Tomioka Giyu and and Kocho Kanae. Giichi and Yumi are obsessed with crows that they insisted in wearing black, as they are known to be considered as Raven Twins.