Byakuya Kuchiki vs. Kōga Kuchiki

is a fight that takes lace during the Zanpakutō Rebellion in which Byakuya Kuchiki reveals his true motives behind his apparent betrayal and defends the honor of the Kuchiki Clan.

Prologue
After being freed from his seal by his Zanpakutō spirit, Kōga Kuchiki breaks his sword and and calls Muramasa nothing but a tool. He berates him for not coming when he called him all those years ago when he was being sealed. Muramasa explains that he did not hear Kōga and wanted nothing more than to lend his powers to him. Kōga, not listening, goes to finish the injured Muramasa off but is stopped by Byakuya Kuchiki, who says that he cannot believe he called his sword nothing more than a tool. Kōga scowls and Byakuya says that Kōga does not deserve the title of Shinigami.

The two back away from each other and Kōga notices Byakuya's scarf and kenseikan. He reasons that Byakuya must be from the Kuchiki Clanand Byakuya says he is the 28th head of the clan. Noting the 28th, Kōga says it has been a long time since he was sealed. He asks if Ginrei Kuchiki is still alive but Byakuya says it would be best if Kōga did not speak his name because after tarnishing the family's name, he has no right to speak of it. Ichigo Kurosaki and Rukia Kuchiki wonder what is going on but Senbonzakura tells them to just watch and that it is a battle for the Kuchiki family honor. Ichigo wonders what is going on as Senbonzakura was under Muramasa's control. Senbonzakura says that he was but when he and Byakuya first clashed, Byakuya fired a Kidō spell across his face, freeing him from Muramasa's control. Senbonzakura says that Ginrei had told Byakuya of Muramasa and Kōga and told him that should Kōga ever be freed that it is his duty to kill him once and for all. Byakuya had infiltrated the library in order to find records on Kōga but there were none. Rukia says she cannot believe that Kōga was once a member of the Kuchiki. Ichigo yells that they should have told everyone but Senbonzakura says it was all for the sake of finding where Kōga was sealed and thus he pretended to still be under Muramasa's control but when he could not get Kōga's location, Byakuya had to get close no matter how it appeared. Ichigo asks why they went so far and Senbonzakura says that it is simply Byakuya's duty.

Kōga asks if Byakuya plans to seal him again but Byakuya says that Kōga must die here for tainting the family name. Kōga says that Byakuya is arrogant enough to be a Kuchiki. Kōga says that if Byakuya really is the head of the Kuchiki clan than he has enough reason to fight him. Muramasa gets up and tells Kōga to use him but Kōga simply picks up his sword and chops it in half. Shocking everyone and causing Muramasa to fall. Kōga says that Muramasa will only get in his way and that he has no need for a weak katana. Ichigo yells at Kōga asking if he even knows what a Zanpakutō is. Kōga repeats that a Zanpakutō is merely a tool and he can always replace it. Muramasa then loses control and his surge in Reiatsu causes a group of Gillian to appear. Byakuya calls him foolish and goes to defeat the Gillian but Ichigo gets there fist. He tells Byakuya to leave the Gillian to them and to go teach Kōga a lesson.