Character profile
Aozaru
蒼猿Biography
Aozaru is the blue monkey associated with Kei's sword, appearing to taunt Youko and prey on her doubts.
Story spoilers
He is the physical manifestation of the sentient spirit within the Suigūtō's scabbard, which was made from a long-tailed monkey demon. When Youko loses the scabbard, Aozaru is free to act independently; she eventually overcomes her doubts, kills him, and retrieves the dead scabbard.
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