is the captain of the 6th Division in the Gotei 13. His lieutenant is Renji Abarai.
Byakuya has slate gray eyes and long black hair, which he keeps up in intricate white headpieces called kenseikanthat symbolize his nobility as the head of the Kuchiki family, one on top of his head and another on the right side. He wears the standard captain uniform along with a white scarf made by the master weaver, Tsujishirō Kuroemon III. The scarf is made from the silver-white, windflower light silk (ginpaku kazahana no uzuginu) and is a family heirloom that is handed down from generation to generation and is given to each Kuchiki family head. The scarf alone is worth enough to buy ten mansions in the Seireitei. He also wears fingerless white tekkou that cover only the back of his hands.
Byakuya Kuchiki is the 28th head of the noble Kuchiki clan, one of the four great noble families in Soul Society. As such, Byakuya acts in an aristocratic manner — he seems always serene and apathetic towards other people, even when he is actually deeply conflicted. He is also extremely calm, even in battle, and is very seldom surprised by even the most drastic of actions. However, when he was younger, he was quick to anger and very hotheaded, as noted by his grandfather. Due in part to his status in Soul Society, he generally acts indifferent, bordering on arrogance, to most situations that he is faced with as seen from how he rarely views his opponent worth his time. Despite this trait, Byakuya is a very perceptive man and is fully aware of the limits of his abilities and usually anything he states in comparison to an opponent is justified.
Byakuya strongly believes in law and order. As the head of one of the great noble families and as a captain in the Gotei 13, he always works hard for a peaceful society. He feels that if someone in his position does not follow the rules as a good example, then no one will follow them. He believes that to maintain the order, all law-breakers must be punished, even if that goes against his own wishes. In spite of his icy and regal manner, Byakuya cares for and protects those important to him. After the events of the Aizen incident, he admitted that law isn't perfect and became more lenient, as well as more protective, of his adoptive sister, Rukia.
Having descended from noble stock, Byakuya is easily offended if his name is not used properly. As such, he views Ichigo Kurosaki in disdain for always referring to him improperly, although he has never said anything to him to change that. On one occasion, Byakuya calls Ichigo to his mansion in order to have a talk with the young substitute Shinigami, but they were interrupted by Yachiru's appearance, who asks Ichigo to follow her elsewhere. After Ichigo's disappearance, it is revealed that Byakuya wanted Ichigo to refer to him properly, and to stop calling him by only his first name. When Byakuya talks with Ichigo, he calls him by his full name, Ichigo Kurosaki.
Byakuya has shown open disdain for those who have been disgraced or who he finds to be annoying or overconfident. This is shown when he uses unnecessary force against Ganju Shiba, who was little to no threat to him, just because he was a member of the formerly noble Shiba family. He also shows that he bears a grudge toward Yoruichi Shihōin for being better than him at Shunpo as well as annoying him by constantly rubbing his face in it, with this particular grudge spanning 110 years. This goes even as far as him even disliking having to use techniques taught to him by Yoruichi.
Byakuya was born into the Kuchiki family, one of the four noble families. Byakuya grew up in the Kuchiki mansion in the Seireitei of Soul Society. He would spend countless hours training, in preparation of taking over the leadership of the Kuchiki family and the 6th Division from his grandfather, Ginrei Kuchiki.
Yoruichi Shihōin appeared to be on good terms with the members of the Kuchiki noble family, as she would often visit the Kuchiki manor to play tag with Byakuya. On one such occasion, approximately 110 years ago, she is presented to a training Byakuya by his grandfather Ginrei Kuchiki, the head of the Kuchiki family as well as the 6th Division captain. Upon seeing the arrival of Yoruichi, he swung his sword at her and called her a demon cat. Yoruichi laughed and playfully began to tease him, calling him "Little Byakuya," complaining about why she received such a greeting after she came all the way there to see him. Byakuya yelled at her that he would never want to see the likes of her and that he will be the head of the Kuchiki clan soon enough so he has no time to waste on her. This prompted Yoruichi to steal the ribbon holding his hair back, Byakuya reacted by quickly turning and swinging his sword at her, but she used Shunpo to move to the roof of a nearby building. Yoruichi laughed at him and exclaimed that if the head of clan Kuchiki could get his hair tie stolen by a girl at play, then she would worry about the future of the clan. Not to be defeated so easily, Byakuya told her not to move an inch, but before he could finish speaking, she told him that he couldn't catch her just as she used Shunpo again to begin the chase. Byakuya plainly stated that he could see that she wished to incite his wrath, and he promised to make her see the error of her ways, further making the claim that his Shunpo is far superior to the likes of hers.
Fifty-five years ago, Byakuya married Hisana Kuchiki, who was a commoner from Rukongai; therefore, he broke the rules by accepting her into the noble Kuchiki family. Five years later, she became sick and was near death. Shortly before her passing, Hisana asked Byakuya to find and adopt her biological sister, Rukia, whom she had abandoned as a baby. She also made him promise that he would not tell Rukia about her real family, for she believed that by abandoning Rukia when she was younger, she was not worthy to be called her sister.
One year later, Byakuya found Rukia at the Shinigami Academy and immediately adopted her into the Kuchiki clan. By adopting her, Byakuya respected his late wife's final wish, but had broken the rules of his clan again. He later swore upon his parents' graves that he would never break the rules again, no matter what. As a result, he, though entirely apathetic on the surface, is actually deeply conflicted with the matter of Rukia's execution; should he intervene, it would require breaking the promise to his parents and the rules again, but should he do nothing, he would fail to fulfill the last promise he made to his dying wife to protect Rukia as his own sister.
Less than 49 years ago and not long before Rukia joined the Gotei 13, Byakuya became the captain of the 6th Division. Gin Ichimaru became captain of the 3rd Division at the same time, and Gin would commonly start pointless conversations with Byakuya during times they crossed paths.
Senbonzakura (aka "Thousand Cherry Blossoms"; a reference to Yoshitsune Senbon Zakura): A regular katana, with a simple cross guard, which is a simple open frame, much like a four-pane window. It has a white-colored hilt and white sheathe.
Shikai: It is triggered by the command "Scatter"
Shikai Special Ability: In its Shikai, Senbonzakura's blade separates into a thousand slender, tiny blade fragments, which then fly away from the hilt, leaving only the sword's handle in Byakuya's hand. The release can be negated before it completes, such as when Yoruichi Shihōin wrapped the blade in cloth during Byakuya's short battle with Ichigo. However, if the release completes itself, then Senbonzakura is rendered near-unstoppable. While the blades are supposedly too small to be seen normally, they reflect light in such a way as to appear as cherry blossom petals. By swinging Senbonzakura's hilt, Byakuya can control the blade fragments at will, allowing him to shred opponents at a distance and break through almost any defense.
Bankai: Senbonzakura Kageyoshi (akaVibrant Display of a Thousand Cherry Blossoms): is essentially a much larger version of Senbonzakura's Shikai. To activate it, Byakuya needs to drop his sword straight down. The sword phases into the ground, as though it were a pool of water. Energy ripples expand out, turning the surrounding area dark, and within seconds, two rows of a thousand giant blades rise up from the ground. Those thousand swords then scatter and countless flying blades pierce the enemy. No one knows the exact number of blades generated and no one can see the movements of those blades or even dodge them. The number of blades is great enough that Byakuya can use them for defense as well as offense at the same time. He commonly forms them into large masses, designed to obliterate opponents instantaneously. As it moves through the air like torrents of waves, it gives the appearance of cherry blossoms flowing swiftly along with the wind. Byakuya's defensive use allows him to cover himself entirely in these tiny blades, and form a body shield. Unlike his Shikai, his Bankai is entirely mentally controlled. While Byakuya can control the blades with his mind alone, using his hands allows him to do so more effectively, making the blades increase in speed three fold. Similar to his Shikai, its attack is triggered with the phrase Scatter.