For your information, Juugo is the owner of the blood used for the curse seal of Orochimaru. Juugo has the ability to transform into anything he wants to.

However, he has two personalities too. Juugo is really a good man who doesn’t want to hurt anybody. But his second personality is somewhat weird that makes him thirsty of killing someone. This makes a problem of him.

When he saw the clinic of Orochimaru, he thought that it would be Orochimaru who can cure his problem, so he decided to join Orochimaru’s group.

However, he then used by Orochimaru on his experiments that lead to the creation of course seal technique.

As of writing this post, Juugo is now member of the Sasuke’s full platoon.