(This is a time jump back into the Sengoku Period, so I apologise if I misinterpret or miss anything. I also will be using a character that was the wind user in the Sengoku Era that is Sanemi's Ancestor I will be naming the Wind Swordsman from this fandom of the former Sengoku Hashiras ( Kimetsu no Yaiba Narratives: Sengoku Tales), as his name will be Takeshi Hayate. So all credit to the Artist and creator (DaFailure428) on X

( that is Amongst the few slayers that was able to master breathing techniques back then, following with The Rengoku clan as well. Another thing, I will be extending the life when the hashiras gain their marks to an older age from 25-50 years old or something like that. 

So this will be not be completely accurate to the Demon Slayer manga, but I'll try my best to make this interesting and engaging. This isn't historically accurate. Enjoy!)

~*~

THE MIZUTSUKI RESIDENCE ~ IN THE SENGOKU PERIOD ~ (Third POV:)

"Lady Ryujin, I've been looking for you!"

The young woman turns around lowering her wooden blade down, taking a moment to breath steadily. Her eyes follow the voice of one of her maids, as the young eighteen year old gave her a gentle nod. "I apologise madam Rina, is there something I may help you with?" Ryujin asked her, with a gentle and indifferent tone.

"Well, your father wishes to find you a suitable match for a husband......" Rina spoke up, timidly whilst keeping her eyes upon her masters daughter. ".....you're the last of all three sisters, to be married and become the Chieftess--"

Ryujin's brow furrowed, "I decline the meeting, I'm not ready....." before walking over to place her wooden blade to the side, as she unties the straps around her Kimono sleeves. They flow down covering her calloused hands, that held every bit of her hard work in her training. "He should know better that I'm not capable of marrying for money or to ally with a powerful clan."

The maid was getting rather anxious the more she stood there, knowing she'll get an earful from the Chief of the Mizutsuki clan soon enough. 

"You declined a potential husband, from the Tsugikuni clan......?" Madam Rina pouted, with a straight posture. Tapping her chin in deep thought, ".....what was his name again, um.......I know it starts with an 'M'......what was it..."

"That was three years ago......and many other candidates that didn't last," Ryuji sighed, while washing her hands carefully so her sleeves wouldn't be drenched. "By the way his name was Michikatsu, but he's married with a child already......"

"Michikatsu! That's right!" Rina exclaimed, a little too late. She gazed upon her mistress, and lamented with a soft groan. "Please Ryujin, your father terrifies me every time I tell him you won't be present or you decline another offer.......you will have to marry eventually."

Marriage was all the same for women during that time, and the time before the Sengoku period and so forth. Ryujin has heard many times, but she never really connected with men at all nor felt desirable to the eye. She struggled having been kept in her room at all times, but slowly as she grew up she decided to try and make a difference and ignored all warnings. She suffered consequences over the years, and still does now. 

"Why not the Rengoku family, their son is a few years older......" Rina suggested, while following her mistress' movements.  "They are also excellent swordsman.......and--"

She paused when her eyes met Ryujin's deadpanned look, glowering upon her maid. Rin chuckles nervously with her shoulders slightly, before bowing her head apologetically. 

"Apologies Lady Ryujin......" she sighed in defeat, and remained quiet while Ryujin walks out along the verandah towards the front gates of the residence. The maid was wondering where she was going, picking up her pace following her mistress at a close distance. "Where are you going now?"

"Out, I wish to meet with a friend," Ryujin replied, keeping her focus steady forward. The residence was bustling with clan members, and a few bowed respectfully with her strong presence. All female respected her. "If you wish to tell about my whereabouts, there are no secrets.......so gossip if you need."

Rina grimaced slightly with a wry smile, "Please My lady, I do not wish to be a talebearer......I merely worry when you go alone," she expressed her concerns, before realisation hits her. "Wait, is this friend......a male acquaintance perhaps?"

Ryujin paused in her steps glancing over her shoulder, "Well, you could say that.........nothing more than just acquaintance's," she cleared her throat, with a subtle nervous swallow. "His name is Hayate Takeshi........a swordsman, I've mentioned him a few times......and the rest of the other swordsmen."

"Wait, you mean......the men Lord Yoriichi trained?" Rina's interest peaked, her soft brown eyes glint in the light. "But the battlefield is no place for a young lady, we can't risk losing the heir to the clan to something the men can handle. Women have limitations, you must know that--"

Ryujin's eyes hardened, "Please, I don't wish to argue over such minuscule disputes," before she continued walking towards the front. She steps down slipping on sandals and taps them to adjust them to fit snugly, and turns to her maid with an indifferent expression. "What women have to go through, is never justified......our thoughts and feelings aren't validated. You of all people, should know the difference of the limitations we have," bowing her head. "I'll take my leave, if I must follow the consequences.....so be it."

With that Lady Ryuji left the residence, leaving her maid behind to stand there in thought. Rina didn't like the fact that her mistress was right, as her hands grip the fabric of her Yukata before turning around with a heavy troubled sigh.

"I understand...."

~*~

AT THE WIND RESIDENCE

"Thankyou, Lord Takeshi...." 

The current Wind Hashira gives her a smirk as he straightens himself, filled with pride when she complimented him. For the past two years Hayate Takeshi became the Wind Hashira, due to his capabilities in performing wind breathing, derived from Sun breathing. A young man and twin brother to Michikatsu Tsugikuni, taught all the Demon Slayers amongst the corps how to use breathing techniques. 

Yoriichi Tsugikuni, wielder of Sun breathing and a very powerful Demon Slayer......

He was missing for roughly a whole decade after the passing of his mother at seven years of age, and soon returned. He began to train all slayers his sun breathing, but none have been able to inherit or even wield the sun breathing technique due to incapabilities. So he had helped modify the breathing techniques to each of their own strengths, which has formed five breathing forms in battle.

............Flame, Water, Wind, Stone and thunder breathing..........

However when it came to her, she struggled finding my breathing technique, as she couldn't handle the requirements needed for each breathing form. Her clan was even against using such breathing techniques, as they only believed in tradition. They never gave it a chance, and Ryujin's father hated the fact that she's part of the Demon Slayer corps as a regular slayer. Her father however was the only male from their family and non-breathing user to be amongst the Hashira. 

"I just........wonder what breathing form, my body can withhold," Ryujin stated; her eyes taking in the whole valley down below the mountain where they both sat. "You're managed to master Wind breathing, so........"

"You'll find it eventually," Hayate assured her, with a wide smirk. He shuffled closer, as his calloused fingers graze her own hand that rests upon her lap. Taking that moment, his fingers interlaced with her own giving it a gentle squeeze. "Once you do, I really wish to spar with you when you find it. It's exciting to even think about........because you're still mastered the way of the blade. Now, you just need to find what calls you........."

He nudged her shoulder gently, with a chuckle.

Ryujin smiled tenderly, "You really believe in me, don't you?........." lowering her gaze, her delicate fingers fiddling with the hem of her Kimono. For a moment in comfortable silence, her Cerulean eyes meet his own. "Anyway, thanks for today.....I really needed it."

He didn't need to know what her family is going through, let alone the pressure that is being placed upon her own shoulders. 

This heavy weight that keeps getting heavier, the more she sees stares, the disgust, disdain, disappointment amongst her own clan and the villagers. She wasn't alone in this situation, but she has endured longer than what her sisters have gone through. Her heart held in the palm of her hand, worried someone will take it away and stab her in the back. It hasn't been safe.......

"I'll see you then in two days time, at noon," he bowed, with a playful smirk. Though in the sunlight of the sunset, she could see warmth and love in his eyes. "I'll be waiting....my Lady."

Ryujin leaves with a subtle flush to her cheeks, and a small smile gracing her lips finding her heart pounding against her chest.

She was definitely falling more in love with him......

~*~

NEXT DAY ~ IN THE CHIEF'S QUARTERS

"I've had enough!!!"

The slam of her father's hand on his desk, didn't make her flinch. Her eyes remain cold and indifferent, accepting his outburst and anger. His thick brows furrowed with an intensity, that could be felt from a few feet away. His posture was slightly slouched but with pride, as he glares upon his daughter.

"You heading out without a guard, and declining my arrangements with potential candidates to take your hand!" He continued on, his finger tapping the edge of his low table. "All your sisters are married, all willing to accept their roles and you? I don't know what makes you any different, but to take upon the role of Chieftess.......your mother had no choice but to marry me. She was obligated to consummate and bare heirs for this family, this clan! I don't need a daughter to make things difficult, than it already has been.......!"

Ryujin's eyes held focus on the floor, not wanting to look at her father. To not see the disgust and disappointment, that has tainted his understanding of her. She had no choice.

"Why make me do the bare minimum?" She uttered out, her fists tightened upon her thighs. Her face slightly darkened, "Can I not run this clan, without needing to find a husband now? Later maybe, but now....I--"

His slammed his palm loudly on the low table, "No! You will marry the next candidate I choose, and this time you'll be married immediately!" He angrily declared, his face growing red with anger. His papers flicker from the neat pile, and the brushes clatter, "Your even lucky to be named Chieftess you know.....many will frown upon you. However, I only choose cause you're the eldest and exceptional at martial arts and wielding a sword......you excel in many qualities a woman should be. You play beautifully with the Shamisen, weaving textiles, and capable to be good at being a political influence........"

Ryujin's throat thickened in response while keeping her head high, but she knew her father listed those qualities to provoke her. To make her feel guilty, being a narcissistic man who gets what he wants.  

"You don't believe that, do you Father?" Her eyes held steady, becoming bold before him. "You want more money, power......it's all the same--"

"And so what if it is?" He remarked, with a loud scoff. "I refuse you to fall in love with a peasant, love is not real. Marriage is convenient for bearing heirs, and extending connections maintaining our wealth. Do you really want to discriminate the Mizutsuki name? Do you think so little us, do you think we have no future? Is this what is it, you selfish wench?"

Ryujin swallowed thickly finding it difficult to breath, tears refusing to fall from his words. She knew her purpose was greater than sitting behind doors, and bearing heirs. 

"How can I be selfish, when you're the one acting selfish," She muttered, bitterly. Her father stood up immediately storming around his desk, "You don't give a damn what I feel, let alone my sist--"

The sound of his hand meeting her cheek was painfully loud, throwing her head to the side causing her head to feel disorientated. She blinks a few times as her eyes hung down, the stinging sensation lingering for longer than she wanted.

"Don't you dare speak to me like that!" Her father roared, furiously. His breath was heavy and ragged, filled with this unnerving rage within him. "I didn't raise you like this! What would your mother think of you, huh? A big disappointment! She's gone because of you, do you understand?! If you won't do what I say, I will have to cut you from the Demon Slayer corps and marry you to a man and keep you locked inside forever! I will not let you ruin our name, because of your selfishness!"

Ryujin just sat there feel utter despondency, still feeling disorientated from his slap which was harder than expected.

This sinking feeling she felt in her stomach gnawed at her, feeling the missing warmth of her own mother. Being reminded of her brought memories that she wished it lasted longer, but using her mother in a way to manipulate her? It made her feel sick. She knew her heart belonged to a man with no status, but a Hashira. Yet she would love to live in life like his, than her own noble home. This endless cycle of women's rights being neglected, despite that women did have a chance being warriors in their time if part from a Samurai clan.

"Don't pull mother into this," Ryujin uttered out.

Her father growled, "Repeat that for me........"

Her cerulean eyes meet his dangerously, "You have no right to use mother.........in this conversation!" She snapped, before standing up tall. Her face was starting swell on her right cheek, but she ignored it now gaining little courage she had. "This is between father and daughter, not her.................so stop guilting me by using her in every conversation! She's not the kind of woman to not love me!"

"Why you--!"

"Lord Mizutsuki...........a message has been delivered," The messenger announced; standing outside with a crow upon his arm. "It's important...."

For a moment her father stood there with a reluctant sigh, "Come in.......and you, be dismissed," he bitterly spoke at the end, his eyes avoiding his daughter's. 

Taking that moment to free herself from her father's arguments, she swiftly walks out and keeps her head down to not alarm the messenger with her face. Once she was out and no one else in sight, tears began to flow down. That painful release she felt tugged on her heart, as she stifled her sobs behind her hand tightly. 

~*~

TWO WEEKS LATER

The burning sensation coursing through her veins.....

She trained her body every day trying to numb every part of herself, blocking out everything that was weighed upon herself. Her body becoming stronger despite her condition, and even Yoriichi has tried to help elevate her pain she felt. Mentally and physically. Though with different backgrounds, he held a level of understanding towards the young woman. She used water breathing to help guide her technique into something new, but to avail she couldn't wield that technique as her own. 

However when she stirs between water and Wind, something formed into something that felt familiar as a child from the Mizutsuki clan.

"Her form.........her blade like the fangs of the beast," Yoriichi murmured to himself, while sat upon the rock. His calm maroon eyes observes her fluid and sharp movements, whilst looking deeper to a spiritual level of her form. Then slowly something surfaces into her technique, locking onto the breathing form she is emanating. "....her body is strong and balanced, yet light on her feet.......her leg acts like the tail of the beast....."

He slowly figured out her breathing style is, after many months trying to help her figure her strengths and ways to help elevate her physical and mental prowess.

"My Lady.........I might've figured something," Yoriichi spoke up, in a soft manner. He watched her slowly come to a pause, lowering her blade and guides back into her scabbard. "Your family is known to have the strength of the Water Dragon.......a powerful being, and by how you've trained during the past few months.....you've utilised that technique. You've honed something, just by seeing your aura within."

Her breath hitches slightly, "Wait, so you can finally......see my strength?"

Yoriichi nodded his usual reserved expression, "It seems for you, that your strength I've been searching was tucked away inside......" he rests his hand upon his chest. ".....but something doesn't make sense for to me...."

Her brows furrowed, "...and what's that, may I ask?"

He sighed deeply, "That birthmark on your left cheek at the corner of your eye......." he murmured in deep thought. "Recently many of the Slayers who have unlocked their markings, either have passed.........or their fates are sealed to live shortly. Though you've never fought intensely with this........breathing technique, I have a feeling about something. I'm not sure yet, but.........I'll look into it."

Her fingertips brush across her birthmark beneath her left eye, that was shaped of the waning crescent moon. 

She could tell that he was troubled by this, but mostly seen the disappointment as each few slayers who gained the mark lost their lives no longer than 25 to an unknown age. It was unknown the lifespan of a person, but the power itself took it away like that by trading power for a life. She greatly admired him for his power, but also how humble this man was. She knew the tragedy he went through, and understood the pain of loss. 

"This birthmark is the first in my clan, to inherit," She spoke up, her eyes met his own. "My mother and her mother before me.........no woman except me has inherited this. Its strange how its a symbol of our family......."

"I assume its the similar case to my mark on my forehead," He mentioned, gesturing to red flame mark that graced his pale complexion. "However.........it doesn't seem yours is inhuman, so i will have some time to figure it out."

Bowing with gratitude she smiled softly, "Thankyou Lord Yoriichi, I appreciate your help......" Ryujin gazed at him, with tenderness in her cerulean eyes.

~*~

A MONTH LATER

"This is the son of a Samurai family, introduce yourself,"

Ryujin's heart sank further while standing before the young man, as her father introduces her to well built swordsman. He was taller than her own father, and his eyes were a steel blue with dark long raven hair in a ponytail with some wave. "My name is Hotaru Takahashi, it's a pleasure to meet you......My lady," He bowed, with respect.

She bowed in respect, "It's a pleasure, I'm Ryujin Mizutsuki......"

Ryujin felt her world spiralling to the unexpected visit, as her father had finally made a choice and found someone who will take the Mizutsuki clans name which was uncommon. However seen he couldn't bear any more children, he relied on his own daughter's name to keep the Mizutsuki clan to live on.

"This young man will be who you will be marrying," Her father informed her,