Byakuya Kuchiki vs. Sode no Shirayuki is a fight taking place during the Zanpakutō Rebellion. It details the conflict between him and the Zanpakutō of his sister, Rukia Kuchiki, as ordered by Muramasa to prove his loyalty to their cause.
As Byakuya Kuchiki arrives at the Zanpakutō cave, he is instantly surrounded by the materialized Zanpakutō, who wonder why he has arrived. Senbonzakura then appears, and asks Byakuya directly why he saved him. To this, Byakuya merely responds that he was moving as his pride dictated. Kazeshini laughs, refuting Byakuya's reason for betraying the Shinigami. 
The other Zanpakutō express their doubts over Byakuya joining their cause, as it would defeat the purpose of repressing their masters. Senbonzakura approaches him and tells him that he is to perform a task in order to prove his complete dedication to their rebellion, to which he asks what he should do. Senbonzakura glances to his left, and tells him to kill his sister's Zanpakutō, Sode no Shirayuki, before them. Sode no Shirayuki protests, as the other Zanpakutō quickly turn on Byakuya, assuming that he doesn't have the heart to destroy his sister's sword.
However, Byakuya ignores their goading, and uses Shunpo, proceeding to attack Sode no Shirayuki. She draws her sword as Byakuya pushes her away onto a nearby rock platform. They clash in mid-air, as the other Zanpakutō wonder whether his attacks are serious. He then pushes her backwards, crashing into a stalactite on the ground, and attempts to attack once again. However, she sends a large amount of ice hurtling towards him, causing him to fall back.
He shatters the ice easily with his blade as Sode no Shirayuki appears from behind him, using Tsugi no mai, Hakuren, which completely immerses Byakuya. However, he destroys the ice forming around him with Hadō # 4 Byakurai, forcing Sode no Shirayuki on the move once again. They clash in mid-air once more, with Sode no Shirayuki blocking most of his attacks. She states that even if he put his all into the fight, it would be impossible for his victory. She uses Some no mai, Tsukishiro, as Byakuya keeps his distance from her attack, continually evading the multitude of ice towers she forms. He reaches the end of the cavern and she leaps into the air, utilizing the attack once more as the ice envelops around him, solidifying. The pillar then cracks into pieces, as Sode no Shirayuki assumes victory over Byakuya. However, he tricks her by using Utsusemi, and appears completely unharmed by her attack.
He then proceeds to bind her withBakudō # 61 Rikujōkōrō, taking her by surprise. As Byakuya moves slowly down the ice pillar, he divulges to her that there is nothing he won't kill to protect his pride. He then slashes diagonally across her waist, causing her to revert to a broken Shikai state. The ice pillar then plunges into the body of water below, as Sode no Shirayuki's broken form clatters onto the surface. Senbonzakura retrieves the broken katana, as the other Zanpakutō watch on in shock.
Byakuya then returns to the side, as Kazeshini comments on whether he is crazy. He mistakes Byakuya's statement as derisive, and proceeds to attack Byakuya, but is stopped by Muramasa. Muramasa approaches Byakuya, finally understanding how strong his pride is. Senbonzakura examines the broken Sode no Shirayuki, and accepts his betrayal, but gives him a warning: Should he act even the slightest bit suspicious, he will kill him. Muramasa tells Byakuya that if he is willing to stay with the Zanpakutō, then he has a job for him.