Board Thread:General Discussion/@comment-5218928-20140305213023/@comment-1387259-20140306055548

Kibaou wrote: So not only Hihiou Zabimaru and Fuji Kujaku are related, but all Zanpakuto are related in a since that they all might react in a way when their names are said wrong.

This isn't really true. Again, Zabimaru withheld something from Renji, and basically gave him a fake Bankai name. Kujaku (the spirit itself) is just stubborn, and the fake name was actually given by Yumichika because he's equally so.