Bleach's Biggest Mystery: Was Yachiru Kenpachi's Zanpakuto Spirit?

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In Bleach, the rank of Soul Reaper Lieutenant is one that carries immense weight. These individuals are usually surpassed in power only by the Captains. In the case of Squad 11, however, their Lieutenant was, for the longest time, a deceptively powerful little girl. Yachiru Kusajishi was her Captain Kenpachi Zaraki's constant companion until she disappeared under mysterious circumstances during the Thousand Year Blood War. Ikkaku Madarame, Squad 11's Third Seat, replaced her as Lieutenant at the Bleach's end.

Yachiru's absence at the end of the series stands out because she didn't lose her life in battle, but rather simply faded away, leaving behind her uniform and badge, in Chapter 579. Her disappearance coincided with Kenpachi's defeat of the Quincy Gremmy, but there was no good explanation for what had happened to her. Then, in Chapter 668, Yachiru seemingly reappeared to Kenpachi as he laid on the ground near death, after attempting to fight the Quincy Gerard Valkyrie. At this time, Kenpachi finally gains access to his Bankai, but most sources refer to this being not as Yachiru but as his Zanpakuto, Nozarashi. They may well, however, be one and the same.

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Yachiru's seeming reappearance is very brief, and not a lot of context is given for exactly whether it's her or not. That said, if indeed Nozarashi is a separate being, and it was imitating Yachiru, it got down her mannerisms perfectly, going so far as to call Kenpachi «Ken-chan». Kenpachi also refers to the being as Yachiru when it first appears, and questions where she had gone. Of course, the very fact that Yachiru disappeared before all this occurred lends credence to her and Nozarashi being one and the