Naraku (奈落?, "Hell") is the main antagonist of the series, having caused the misery of most of the main cast. He was born fifty years ago from the desires of a gravely burned bandit named Onigumo (鬼蜘蛛?, "Oni Spider"), who was found by Kikyo and his wounds tended to. As the injuries had severely crippled him, Onigumo forms a pact with the surrounding demons attracted to his darkness to consume him in return for his soul to occupy a new body created from their merged bodies so that he could satisfy his frustrated lust for Kikyo. However, with Onigumo buried deep in his subconscious, the newly born Naraku acted against his human self's desire as he arranged for 's demise and her falling out with Inuyasha in the expectation that events would corrupt the Shikon Jewel. But when Kikyo had the jewel burned with her corpse, Naraku bides his time until the Shikon Jewel is brought back to the feudal era by the priestess's reincarnation Kagome. Naraku also learned of Inuyasha being freed from his seal and traveling with Miroku, attempting to enlist Sesshomaru's help before revealing himself.
While Naraku originally appears in the form of a hooded figure wearing a robe made from a baboon pelt, which is also utilized by his Golems (傀儡 Kugutsu?), he later permanently assumes the guise of the young lord Kagewaki Hitomi (人見蔭刀?). After his body is heavily damaged by Kagome when he attempts to use Sango's brother Kohaku against her, Naraku heals his body by locking various demons in a mountain to engage in a death match before absorbing the winner after it assimilated its defeated opponents. Soon after, receiving Shikon Jewel Shards from Kikyo, who realizes that he desires it to become a full demon, Naraku gains the ability to create his incarnations. Eventually, after losing the Hitomi clan castle, Naraku takes refuge in Mount Hakurei and tricks the priest Hakushin into creating a powerful, holy barrier around the mountain to conceal his presence from his enemies while resurrecting the Band of Seven to hold off them off. By the barrier around Mount Hakurei is dissolved, Naraku appears in a new form after having removed his heart and splinter it into two pieces: his physical heart placed within the newly created Infant while his human soul is left within the ruins of the mountain. This act enables Naraku to mortally wound Kikyo without Onigumo's presence to hinder him and with power nearly equal to that of a full demon. The removal of his heart also rendered Naraku invincible, unless harm comes to the Infant as he conceals the infant while personally go after the remaining Shikon Jewel shards.
But having suspected the Infant would turn on him, having absorbed a barrier-destroying tree demon known as Yomeiju, Naraku allowed the Infant and his vessel Moryomaru to do as they will before tricking the latter to devour him so he can absorb his heart. But when Naraku learns of Kiyo's intent to purify him and the completed Shikon Jewel, knowing his human self's darkness would be a countermeasure, Naraku is forced to reabsorb Onigumo's soul before Kikyo finally dies in the battle that ensued. With only Kohaku's Shikon Jewel shard left, ignoring the speck of purity within the nearly completed Jewel, Naraku focuses on getting the boy with the aid of Magatsuhi. Once completely restoring the Shikon Jewel, Naraku creates a giant spider-like body around himself as he attempts to have Inuyasha's group and Sesshomaru destroy whatever speck of light remained in the jewel. It was during the final battle, as it concludes around Kaede's village, that Naraku uses the Shikon Jewel to become demonic version of himself. After his body was destroyed by Inuyasha's multiple barrage Meido Zangetsuha attacks, both Inuyasha and Kagome asking him what he was after and his methods to sever bonds between people, Naraku realizes that he desired Kikyo's heart before the jewel is purified and his body destroyed. Reduced to a head and near death, Naraku makes a wish that Magatsuhi desired to bring himself and Kagome into the Shikon Jewel's world to become part of it once the girl makes a selfish wish to complete the act. Luckily, Kagome uses her wish to have the Shikon Jewel cease to be with Naraku fading with the jewel and its trapped occupants.
Naraku's basic abilities are shape shifting and absorbing his opponents, later gaining new abilities as he enhances himself over the course of the series. Unlike other half-demons, Naraku can choose what time of the month he loses his demonic powers where he is reduced to a human head attached to multiple demons, using that form to remove demons he considers weak from his body as part of his self refinement. But, to his distaste, Naraku permanently has a spider-shaped birthmark on his back that is a constant reminder of the humanity that constitutes his being. Naraku possesses several poisonous abilities, such as producing a deadly Miasma (瘴気 Shōki?) and the poisonous Saimyōshō wasps, the latter used chiefly to prevent Miroku from uncovering his Wind Tunnel.
- If you destroy Hitomiko with your Sacred Arrow her Soul can never be saved. The Priestess will die a Demon. And so will her Soul. Which means it will be cursed to join my Spider Webs in the fires of Hell for all eternity.