"Nii-sama!"

Byakuya gave a mental sigh and prepared himself for the small ball of energy and chaos known as Kurui. His peace and quiet came to an end the moment his younger sister spotted him stepping through the gates of their family manor. He stopped in his tracks and saw a little girl bounding up to him, allowing the child who hasn't even reach his waist to hug him around his legs the moment she reached his side.

"Rui, I am busy."

"You are always busy." Kurui gave a pout that immediately weaken his mental defences. "Spend some time with me! I'm boooooooreed."

"Have you finished your homework?"

"Nope!" Kurui chirped back happily. "Who cares about these boring stuffs anyway? Not like I will have to apply whatever was taught."

"Rui." Byakuya resist the urge to rest his palm on his forehead. Why? Why had his parents left him with a younger sister just right before they passed on? Why is he the one in charge of raising his sister? He is only in his teens.

"Nii-saaaaamaaaaa."

"Rui, don't bother your elder brother."

The voice of the 27th Head of the Kuchiki clan can be heard as Kuchiki Ginrei appeared beside them in a shunpo. His firm and wrinkled hand rested on Kurui's shoulder before he gently pulled her back to his side.

"Sofu." Byakuya greeted his grandfather politely and respectfully with a bow. His stern grandfather is the only one who can handle Kurui. The remnants of his peace and quiet can still be salvaged with him around.

It's not like Byakuya don't love his sister. On the contrary, he loves his sister dearly, but she has way too much energy for him to keep up. He has no idea who she took after in this regard. None of the members of their family is as hyperactive as his little sister.

His mother would definitely love her if she was still alive. The same goes for his father too, but they are already dead. They died not long after Kurui was born into their family. It was a mission went horribly wrong that claimed both their lives. His father was supposed to take over as the 28th Head of their clan, but his untimely demise had forced his grandfather to continue to lead the clan despite his old age. Now, the only candidate to be the next head of their clan is him, Kuchiki Byakuya. The future of his clan rest on his shoulders now.

And because of that, he hardly has any time for Kurui. Training under his grandfather on top of his duties as a Shinigami makes him an extremely busy man. He feels a little guilty for it. He is her elder brother and he knows just how attached she is to him and their grandfather.

If only his father was still alive, he would have more time for Kurui. If only his parents were alive, Kurui would be able to know what parental love is. They are no longer able to protect her now, so he will do it in their stead.

He will never let any harm befall on her.

Even with the stern and stoic mask that his grandfather always wore on his face, it is obvious that his grandfather has a soft spot for his youngest grandchild as well. Kurui never fails to brighten up their day and made the otherwise quiet manor a lively place. She is their sunshine.

Despite their love for Kurui, the one thing that he and his grandfather can never seem to drill in Kurui's head is their family's insistence on rules and order. Kurui is brought up the same as he was and was taught the same teachings as he had learned, but somehow, Kurui never turned out the same as the other members of their family. She defies every single rule that is put in place. She never went to bed when it is time to do so, she never greeted people with the proper honorifics in a formal setting no matter who they are, she never bothered to carry herself as a dignified noble lady no matter how much he and his grandfather had stressed that she has to, because she is a Kuchiki.

She is everything that a Kuchiki shouldn't be. Yet, it feels as if she belongs here all along. No matter how un-Kuchiki she is, the same Kuchiki blood run in her veins just as it run in him.

"Sooofuuu." Kurui whined as she tugged on the sleeves of their grandfather. "No more studying! Pleeeeaaasseee?"

"Your calligraphy-"

"It's not like I will be wielding a brush in battle when I become a Shinigami!" Kurui exclaimed with her hands flailing animatedly in the air. "Who even needs calligraphy skills in battle?!"

"You are a Kuchiki. As a lady of noble birth, you need to learn-"

"SOOOFUUUU~~~"

Ginrei gave an audible sigh of resignation. He may be the head of the clan and the Captain of the Sixth Division, he may be the strict and stern warrior that both his subordinates and enemies fear, but somehow, none of this matter in the face of his granddaughter. He just can't seem to be able to get her to act like a noble that she is born as. In front of her, he is just a grandfather that can't help but dote on his granddaughter.

"How about this? If you can catch me with your shunpo in a game of tag within ten minutes, then you will be excused from your homework for the rest of the day." Byakuya came to his grandfather's rescue and he can see the elderly man giving him a brief yet grateful look his way. "If you can't, then you will go back to finish your homework. Deal?"

Kurui immediately dashed from their grandfather's side in a burst of speed to attempt to tag Byakuya with a surprise attack, but Byakuya had saw it coming and disappeared with his own use of shunpo.

"I haven't said start yet."

"Nii-sama! Don't run! Stay right there and let me tag you!"

Ginrei walked back to sit on a wooden chair nearby and let a small smile rest on his face as he watches his grandchildren interacting with each other. Kurui is smart, extremely so. She must have known that she stands no chance in catching Byakuya with her current proficiency in shunpo, but she still tries anyway.

She just wants to spend some time with her brother.

As souls, they age differently from humans. The stronger the Reiatsu a soul has, the slower their aging process is. If he has to estimate Kurui's age using human's growth rate as a measuring stick, then Kurui is probably only about five to seven years of age although her small size makes her look even younger than she really is. Even then, her shunpo alone is scarily good and that is not considering her skills in using Kido. Even he didn't have the same proficiency as she did when he was her age. Her Hakuda and Zanjutsu are still lacking, but that is to be expected since she is still young.

If only Sojun, his daughter-in-law, and his wife are still alive, they would be proud of Kurui's achievements. His son and daughter-in-law will definitely smother Kurui with love and his wife will definitely spoil her. Kurui will have them wrapped around her little finger and they will not be able to resist.

"Nii-sama! Get back here!"

Ginrei watched on as Kurui chased after Byakuya, who maintains a fixed distance away from her. It seems that Byakuya's shunpo has improved, and so did Kurui. Byakuya's growth is expected, but Kurui? He wasn't expecting her to be able to keep up with Byakuya for as long as she did. Did she practice shunpo on her own without them knowing? Since when did she became so good at it?

"Time's up." Byakuya stated as Kurui simply collapsed and lay on her back panting for breath in a very un-ladylike manner. Both Ginrei and Byakuya frowned at the sight, but they know by now that it is a lost cause trying to lecture the youngest Kuchiki about her behaviour.

"Rui, at least try to sit up." Byakuya commented as he walked towards his sister before stopping a few steps in front of her. "It is unsightly to lie on your back like this in public."

"Don't' wanna~" Kurui sang back playfully with her long black hair splayed out on the ground around her. "And we are at our own home, not in public. I can do whatever I want in my own home."

In response, Byakuya plucked Kurui off the ground by grabbing the back of her kosode and lifted her up with one hand.

"You will catch a cold if you continue to lie here. If you want to continue to lie on the ground, at least do so in your own room."

"Nii-sama! Don't pick me up like a disobedient puppy! This is unsightly!"

"Now you are talking about what is unsightly and what's not?"

"Nii-sama! I am a girl! A lady! I should be treated like a queen, not a puppy!"

"You never act like one."

"I do!"

Ginrei shook his head with fond exasperation as his granddaughter bicker with her older brother. Kurui absolutely adore her older brother and Byakuya loves his younger sister deeply. He can still remember the time when Kurui was a toddler and she followed Byakuya everywhere, trying to learn and mimic what she saw he did.

"Go get yourselves changed." Ginrei broke the argument between the two siblings as he spoke in his deep voice. "It will be lunch soon."

"Yes, sofu." The siblings answered in unison before excusing themselves, with Byakuya carrying his sister back to her room with a piggyback, much to her delight.

He may have lost his son and daughter-in-law, but they left him with the best grandchildren he can ask for.

He will not let anything happen to them.

Byakuya sighed once more as he gently carried his sister in his arms. As per their agreement, Kurui has to finish her homework since she lost in their game of tag earlier. She had started on her calligraphy after lunch, but apparently this subject is too boring for her taste given how she had dozed off halfway into practising her brushstrokes and planted her face on the paper still wet with ink.

Byakuya slowly place his younger sister on her bed and used a clean cloth to wipe away the ink stains on her beautiful face. Her face shape and hair definitely took after their father, just as he did. However, her eyes are undoubtedly their mother's.

He can already see that Kurui will grow into one of the most beautiful women in Seireitei's history, just like their mother.

Byakuya turned around the moment he sensed his grandfather's presence, who put a finger to his lips in the gesture to keep quiet the moment he entered the room. None of them want to wake Kurui up from her sleep.

"She has worn herself out in the game of tag earlier." Byakuya said to his grandfather the moment the both of them left Kurui's room after tucking her in comfortably. "She had obviously put a lot of effort in practicing her shunpo in the days that I didn't see her. Her improvement is certainly shocking."

"She did." Ginrei confirmed. "Although I have no idea where she finds the time to do so. If she is not running about skiving off her lessons, she would be trying to find a way to exit the manor to explore what is outside."

Byakuya allowed a small smile on his face as he imagined his younger sister giving the entire manor a headache with her constant efforts in trying to sneak out undetected. There were a few times that she nearly succeeded, much to their horror.

A silence settled between the two of them before Ginrei spoke up once more.

"I am thinking of starting her on the more advanced aspects of the combat arts. She tends to avoid her homework, but she is smart. She may even surpass me one day."

"I have no doubt she will." Byakuya stated confidently. "She may slack off in her theory lessons, but she is a hard worker when it comes to learning and perfecting the four major combat forms. She will grow to be the strongest Kuchiki in our clan's history."

"You will too." Ginrei added. "You and your sister will be the greatest warriors in our clan's history."

The two of them entered Ginrei's study. Now that Kurui isn't here to distract them, they can finally start the lessons proper. There are still many things that Ginrei have to teach Byakuya before he can take over as the 28th Head of the Kuchiki clan.

"Ye lord! Mask of blood and flesh, all creation, flutter of wings, ye who bears the name of Man! Inferno and pandemonium, the sea barrier surges, march on to the south! Hado #31: Shakkaho!"

Ginrei watched with unconcealed pride as his granddaughter successfully pulled off a Shakkaho. She has a very good grasp in controlling and utilising her Reiatsu, which is an immense boost in helping her master the Kido and Hoho combat arts. Give her a few more years and she could probably use a Shakkaho without an incantation but with the same effect.

He and Byakuya wasn't planning on starting Kurui to learn the combat arts at such a young age. It was just to satisfy her curiosity initially, since she was mesmerised at how Byakuya had done it when she first saw him practicing his Kido. They taught her one of the simplest spells, Bakudo #1: Sai. They weren't expecting her to get the hang of it or to even produce anything that has any resemblance to the spell. It was just to stop her incessant bugging to teach her how to use Kido.

They weren't expecting her to persevere and continuously practice the spell they taught her. By the end of the month, she had managed to successfully use the spell. The power was lacking, but she was very young back then and hence don't have much Reiatsu to fuel the spell. Her success had thrown him and Byakuya in for a loop.

Kurui picked up Kido spells much faster after she got the hang of using Sai. Ginrei and Byakuya also indulged her and taught her Kido spells they deemed safe enough for her to use at her age. Her rate of learning the Kido arts began to skyrocket after that. The same goes for the Hoho arts, where Byakuya personally taught her how to use shunpo.

Such progress at such a young age. His granddaughter is a prodigy. His little prodigy.

"Good job, Rui." Ginrei gave an affectionate pat on his granddaughter's head, who beamed at the praise. "Your mastery over Kido and Hoho is improving nicely. It's time we focus more on your Hakuda and Zanjutsu."

Kurui nodded as they both took a few steps backwards and got into a stance. A nod from Ginrei was all Kurui need as she dashed forward and immediately engaged her elder in hand-to-hand combat.

"Too low." Ginrei pointed out the flaws in his granddaughter's Hakuda as he easily parried a strike to his kidney. "Aim higher."

Kurui did just that but Ginrei intercepted her punch and flipped her over his shouder.

"Remember to not overextend yourself. Be unpredictable."

Kurui did a mid-air flip before landing on her feet. A low sweep of her legs forced Ginrei to jump upwards and Kurui used this opportunity to press on her attack, hoping to get a clean hit in.

"Too much strength." Ginrei caught his granddaughter's fist before punching her abdomen with just enough force to make her winded, but not hurting her. "Don't overcommit unless you are sure that you can take your opponent down in a single hit."

Kurui stood up straight again as she tried to catch her breath at the same time. Ginrei gave her a mental nod of approval at the sight. No matter how hard it seems, his granddaughter had never once backed down. She is a Kuchiki through and through.

The two of them continue to spar in this manner. Kurui's Hakuda is good, but she does not have the same talent in this art of combat as she does for the Hoho and Kido arts. She picked up the latter two as easy as breathing but her Hakuda is just unable to progress at the same rate. Thankfully, her Zanjutsu is more than enough to make up for it.

Kurui was out of breath at the fifteen-minute mark, which is already way past the expectation he has for her. He may not be going all out in their spar and he did not put much strength in his strikes, but he wasn't going easy on her either.

"We will end here for today." Ginrei said as he patted his granddaughter on her back to help ease her breathing. "We will continue to work on your stamina tomorrow."

Kurui's face blanched, but she did not complain. Ginrei knew that his granddaughter isn't exactly fond of physical exercises even if she can understand its importance.

"I will get the servants to make your favourite soup."

Ginrei let out a small chuckle when Kurui whooped in delight. He is her grandfather, spoiling her is part of the job description. He is allowed to dote on her.

"Hey, sofu, will we be practicing with real swords tomorrow?" Kurui asked him excitedly as the pair began to make their way back to the compound where they stay at.

"If you want to, we can." Ginrei decided after giving the request a few seconds of consideration. "It is better to start early than late when it comes to Zanjutsu."

"I wonder what kind of power my future Zanpakuto will have?" Kurui asked aloud. "I hope it doesn't have a lame ability."

"There are no such things as lame abilities, only users who do not know how to use them to their full potential." Ginrei chided his granddaughter and gently knocked her on the head with a knuckle. "Besides, you haven't even mastered Zanjutsu yet. You are still too early to even dream of using a shikai."

"But sofu~~~" Kurui gave her characteristic whine that he has no resistance to. "What if it is just an extremely lame ability like muscle strengthening? Or an ability that simply increase a Zanpakuto's cutting power? It will be so lame!"

"Well then, what isn't lame to you?" Ginrei raised an inquisitive eyebrow at Kurui's remark.

"Like the Captain Commander's ability to summon fire! That's cool! Imagine burning through everything! An unstoppable force of nature!" Kurui began to gesture excitedly. "Or maybe the ability to summon lightning! Move the earth! Complete control over air and water! And-"

"You have a hyperactive imagination." Ginrei said in amusement before ushering her into their house. "Sometimes I wonder where you get this trait from."

"You and Nii-sama are just too boring." Kurui playfully stuck her tongue out before dodging a swipe of his hand to her head. "Really, sofu, you need to learn how to unwind and have fun! You and Nii-sama can just sit still and say nothing the whole day! Someone has to talk!"

"You talk enough for the three of us." Ginrei replied. "Someone has to remain silent on your behalf."

"Sofuuuuu~"

Definitions and meanings:

Kurui: Confusion, deviation, disorder

Sofu: Grandfather

Zanjutsu: Art of the sword

Kido: Demon Arts, a form of combat based on advanced spells

Hakuda: Hand-to-hand combat

Hoho: Fast movement, a defensive style of fighting relating to footwork. Shunpo falls under this category and is the greatest expression of the Hoho technique

AN: There are an increasing number of people asking me to write a story with a female oc as the protagonist. I had always wanted to try writing a fic about the Bleach verse and seeing at how Bleach is so male-oriented, it feels right to write about a female oc. I decided to let Kurui be a Kuchiki since her being one will allow her to interfere with the plot more easily, and because the Kuchiki is a more known and explained family in the Bleach verse as compared to the others. Furthermore, I think seeing Byakuya being an overprotective brother feels kind of amusing.

I'm still a little wary on writing a Bleach fanfic since canon itself is full of holes ever since the whole of Aizen arc is over. But meh, whatever.

In any case, I hope this is a good enough surprise/ fanservice for those who really wanted me to write about a female oc. Hope you guys enjoy it.