Hakudōshi

Hakudoshi was Naraku's eighth detachment, who was actually the other half of the baby Akago. Akago was cut in half by a monk; one half remained a baby while the other grew to be Hakudoshi. Hakudoshi first appeared when the body of Akago was cut into two, him being spawned from the half Kagura was carrying. Nothing was known about the other half as it was in Kanna's possession. Hakudoshi then defeated the previous steed of Entei, and Entei became Hakudoshi's steed. Hakudoshi was then determined to get to the Netherworld, in order to get the last Shikon Jewel Shard, which was in the body of a crystal in The Great Dog Demon's body. he fights Inuyasha 4 times and gets 3 of Kagome's shards.

Histroy
Upon learning the last shard of the Shikon Jewel is in the world between the living and the afterlife Naraku sends the infant and Kagura to kill priests in order to discover a way into the next world. One of the monks they attack manges to cut the baby in half, before he dies. Kanna meets with Kagura and tells her to keep one half of the infant while she took the other half. The half Kagura is charged to watch would grow into the body of a young child. The child would take the name of Hakudoshi. Upon awakening he orders Kagura to bring him new clothes as he had out grown his old ones. The yokai horse Entei follows Kagura and choose Hakudoshi to become his new master. In the anime Hakudoshi kills Entei's pervious owner which earns the demon horse's respect. Shortly after this he encounters InuYasha's group for the first time. He confirms that Narku is indeed searching for way to travel to the world between the living and the dead, and also reveals to them that the last Shikon shard is there, something the group did not know. When Kagura questions him about this Hakudoshi simply replies that he saw no need to keep it a secret. When InuYasha tries to kill him with the Wind Scar Hakudoshi puts up a barrier, and then leaves with Kagura and Entei.

Hakudoshi decides that human priest could not provide him with the location to the world between the living and the afterlife, so he decide that yokai may hold the key. He begins to cut off the heads of demons to search their minds in order to find the way to travel to the next world. After decapitating many demons Hakudoshi finally discovers the location of the next world. He orders Kagura to tell InuYasha and his friends about the location to gate that leads to the world between the living and dead. He intends to use them to battle the gate keepers and use Kagura to see if the gate is safe. Kagura questions Hakudoshi about using her, which he admits to doing. This causes Kagura to attack him, only to discover like Naraku he can simply regenerate. He warns Kagura that he is connected to Naraku and that attacking him will only lead to Naraku to squeeze her heart as punishment.

After Naraku makes a pact with the bird Princess Abi Hakudoshi helps Abi and her bird demons to collect the blood of humans. He briefly battles InuYasha but the hanyo is unable to overcome his barrier, even with the Red Tessaiga. Hakudoshi's barrier is broken by purifying arrow to his surprise, this allows InuYasha to cut him with the Wind Scar. Hakudoshi starts to renenerate, but Entei is killed by the Wind Scar. He orders Kagura to get take him and retreat. while regenerating in a hide out Kagura notice that Hakudoshi does not have a heart, and deduces that his heart is in the infent. Hakudoshi acts as Naraku's connection to the living world when he travels to the world between the living and the dead. When Kagome shot Naraku with one of Kikyou's arrows follows Naraku back to the living world striking Hakudoshi down, however since the baby is the one who poessess their shared heart neither Naraku or Hakudoshi is killed by the arrow.

Forcing Kikyou Out
Under orders from Naraku Hakudoshi along with Kohaku try to lure Kikyou out in the open. The pair kill a rat demon and take his shrine. Hakudoshi opens the shrine releasing a swarm of demon rats that devour anything in their path. When Kikyou finally acts Hakudoshi orders Kohaku to guard the shrine and keep it open, while he goes to deal with Kikyou. He just misses Kikyou, but destroys the tree by using giant slugs she created to purify the rats. He tells InuYasha and Kagome that if they see Kikyou to tell her that Naraku will continue to cause this level of destruction until he finds her. He also retrieves Kohaku and takes him back to Naraku.

Creating Moryomaru
Hakudoshi along with Kohaku hunt down a demon that devours haku the power that moves the body of all living being in the InuYasha world. After killing the demon Hakudoshi takes the haku it had devored to use in his experiments. His experiments involved using pieces of other demons together as a mish mashed from, and using the haku to allow them to move. His experimented demons run around attacking humans and demons alike drawing the attention of both Koga's group and InuYasha's group, who kill all of the mish mashed demons. Eventually Hakudoshi discovers that the closer the created demons were to an human appearance the easier it is for them to move. He perfected creating demons and created Moryomaru.

Hakudoshi decides to test out his creation by having him fight Koga and at the same time try to steal the wolf demon's two Shikon shards. Moryomaru has the upperhand, until InuYasha interferes unleashing the Wind Scar. Hakudoshi protects Moryomaru with his barrier. Despite InuYasha joining the fight Moryomaru hold his own while Hakudoshi watches. By working together the two groups manage to create an opening for InuYasha to use his new technique Kongosoha, but once Hakudoshi steps in to protect Moryomaru despite knowing his barrier would be broken by InuYasha's attack. Unknown to the group the baby urges Hakudoshi to save Moryomaru. Although he fails to steal Koga's shards Hakudoshi manages to gain a small victory by stealing the yoki crystal from Miroku, perventing the group from locating the fuyouheki that conceales the baby's yoki. In the anime Koga is not involved in the fight at all, instead of tracking Koga down Hakudoshi test Moyomaru out on InuYasha, however the fight ends in the same manner as the manga.

After retreating Hakudoshi delivers Moyomaru to the baby and Kanna. He leaves telling the baby to use Moyomaru any way he wants to. He questions Naraku about why he allows Kagura to live even though he knows she is bretraying him. Naraku answer him by saying that he can end Kagura's life anytime he choose because he has her heart and that he(Naraku) needed her for one final job.