Who is zyuubi?

Answer 1

Its "Jyubi"
According to legend :
Jyubi was a Ten Tailed Demon.
Who tried to destroy the World which was captured and controlled by the Rikudou Sannin.
Then he divided that Ten Tailed Demon into nine tailed Demons.
such as one tailed, two tailed and so on till Nine Tailed (Power increase from one tailed to nine tailed; Nine tailed Demon has the highest power hence very near to Ten tailed "Jyubi").
But even after that enormous amount of energy remains which is transformed and made our Moon outta it.

Answer 2

I am not familiar with a character or entity named "zyuubi." If you could provide more context or details, I may be able to assist further.