Kanna

Kanna (神無) s the first detachment of Naraku. She appears to be a ten-year-old girl with white hair and clothing. As a "concealed incarnation" of Naraku, Kanna has no smell and no demonic aura, making her undetectable to InuYasha's senses and immune to demonic aura-related effects such as the Hakurei-zan barrier Kanna is the only incarnation that Naraku trusts with important information about his actions, allowing her to give orders in his place.

Overview
Kanna carries a mirror that can steal the souls of those reflected in it. Once a soul is trapped by her mirror, Kanna can control that person's body to carry out her bidding. However, the mirror can be overwhelmed by an especially powerful soul such as Kagome's and Kaguya, forcing Kanna to release all of the trapped souls before the glass shatters. The mirror can also create a glass demon to copy the abilities of whatever it reflects, though Kanna herself suffers damage when the glass demon is wounded. In her last battle in the manga, Kanna is ordered by Naraku to commit suicide, shattering herself and her glass demon into thousands of tiny shards. Driven by Kanna's final thought, one of the shards hits Kagome's right eye and gives her the knowledge how to destroy Naraku. Kanna's death does not appear in the anime, which ended before reaching that part of the story.

Name Meaning
Kanna (神無) is an old Japanese language word meaning "godless world".

First appearance
In the manga, Kanna first appears in volume 15, scroll 8 "The Mystery of the Wind Witch", page 152. There, Naraku tells Kagura "I have already sent your elder sister ... Kanna.". Then Kanna is seen walking with her mirror and some Saimyōshō towards a village, where she will steal the souls of the inhabitants and turn them against InuYasha and his friends.

Kanna's end
In recent chapters of InuYasha, Kanna becomes more dangerous than anyone expected. She battles the group using a glass demon that came from her mirror. The glass demon copies the power of Tessaiga, robbing it of nearly all of its powers, including the Kaze no Kizu, Crimson Tessaiga, the Dragon-Scale power, and the Kongosōha, leaving the real Tessaiga nothing more than an apparent shell. It also appears that if the glass demon is hurt, the injuries are inflicted on Kanna since a black mark appeared on her neck after Kagome's arrow struck the glass demon in the same place with no apparent effect on it, and the same thing occurred when InuYasha struck the glass demon's left shoulder, which turns the demon into a fighting voodoo doll.

When the group finds Kanna, she fires a ray of light from the sky down at InuYasha. He reflects it with Tessaiga back at the glass demon. Kanna continues to receive damage to herself and the Tessaiga cracks from all of the light blasts. Kagome deduces that Kanna was ordered by Naraku to sacrifice her life in order to break Tessaiga.

Because she continued to take most of the glass demon's damage, Kanna indirectly loses her left hand and right arm during the battle. In chapter 480, she commits suicide, as per Naraku's command, by shattering herself and the glass demon into hundreds of flying shards. A tiny shard manages to hit Kagome's right eye (superficial damage) and through the shard, Kanna communicates to her the secret to defeating Naraku.

Other than that, Kanna has never shown signs of betrayal to Naraku and was his most loyal, trustworthy detachment.

Naraku had commented upon Kanna's death that she had no thoughts and feelings; it was assumed she did not care about either being alive or dying. However, after Kanna had communicated with Kagome just prior to her death, Kagome stated Kanna in fact did not want to die and perhaps had feelings of her own.