Moryomaru
Character Description:
Moryomaru was originally a haku (life-force) puppet created by Hakudoshi and then given to Kanna. Kanna places Akago inside of him (giving the puppet Naraku's soul). He is able to absorb demonic energy, and energy-based attacks against him are useless. He can also take this energy and convert it into a powerful blast (a technique used by Goryomaru while they were attached).
Moryomaru is now really Akago, and the living heart of Naraku. Because of the Fyoheki stone which was given to Akago, his energy cannot be detected by others. Both Inuyasha and Sesshomaru have trouble defeating him because of his immunity to energy-based attacks.
Kohaku attempts to kill Moryomaru after he is told by Kagura that he is after the shard in his back, since his ultimate goal is the destruction of Naraku by the death of Akago (inside Moryomaru). He fails, which enables Moryomaru to almost steal the shard until Sango comes to help. Moryomaru then flees.
