Byakuya, the Truth Behind His Betrayal.Senbonzakura reveals that Byakuya had sworn to kill Kōga and had been searching for how to unseal him, even if that meant risking his status as a Soul Reaper. Muramasa offers Kōga his power, but Kōga breaks Muramasa, stating that he does not need help. Byakuya and Kōga fight, but Kōga gains the upper hand when he distorts Byakuya's senses. Senbonzakura helps dispel the effect though, and Byakuya manages to use bankai on Kōga. As Byakuya notes that Kōga's failing was refusing to trust his zanpakutō or anyone else, the two charge at each other.