The main antagonist, Naraku (literally means "underworld", or "hell") is responsible for nearly every character’s suffering throughout the series. He is a han'you that originated from a bandit named Onigumo ("Demon Spider"). Naraku's main goal is to collect all of the shards of the Shikon no Tama in order to become a full Youkai. His platonic love for Kikyo is what drove him to kill Kikyo and seal Inuyasha on the tree and the basic reason he became a demon.
Kagura (lit. Music of the gods) is a wind sorceress created from Naraku's own body. Despite this, she has her own mind and is willing to fight desperately for freedom. Her first appearance involves Kagura's use of the "Shikabane Mai," or "Dance of the Dead," to lure out Koga's companions and slaughter them. Following this, she splattered Inuyasha in the blood, causing Koga to arrive to "avenge his companions." Unbeknownst to Koga, he has a false Shikon no Tama shard rather than the real one-and upon severly injuring Inuyasha, he is immobilized by Kagura's fake. Assured that she has won the battle, Kagura steps forward to take the real shikon shards as well as Koga's life. This is interrupted by Inuyasha, who proceeds to fight Kagura and is on the verge of being killed when he is finally able to interrupt Kagura's winds to unleash a Kaze no Kizu. Surprised, Kagura flees, briefly showing a spider-shaped burn scar on her back similar to Naraku's. She realizes that Naraku has been using her and proceeds to attack him, being stopped when he squeezes her heart and tells him that he holds her life in his hands. Since then, Kagura has worked to kill him, often using others. Following the first meeting, Kagura encounters Inuyasha and defeats him easily with the help of Kanna. Naraku orders her to carry out much of his work, but does not regret losing her when she openly betrays him. Kagura meets Sesshoumaru and decides his strength is enough to destroy Naraku. She locates Toukijin and tells him where it is, and then watches his fighting skills. Later, when he realizes she is using him, Kagura does not deny it, but rather comes clean about it. Over time, Kagura becomes increasingly reckless in her attempts to kill Naraku and begins to use Inuyasha as a pawn as well. She often attacks Koga, feeling he is useless in her plans. Naraku often teams Kagura with Kohaku to do his jobs. When both realize that the other is also after Naraku's life, they become allies and plot together to destroy his heart. Eventually, Hakudoushi and Moryoumaru come after Kohaku's shikon shards, Kagura protects him at the cost of her own life. Naraku mocks her, giving back her heart and then subsequently poisoning her. Kagura realizes she has a short time to live, and flying away, falls into a field of flowers. There she notices she can no longer move and begins to despair. Sesshoumaru shows up, following the scent of Naraku's miasma and having realized Kagura was in danger. He attempts to save her with Tenseiga, but this does not work. Soon after, Inuyasha's team arrives and Kagura dissolves into the wind, happy to have been able to see Sesshoumaru before she died. Kagura's death supplied Sesshoumaru's heart with enough new feelings to allow the growth of his sword, Tenseiga. The wind blows as he promises to make her death worth something. This same strong, but not dangerous, wind appears to Kanna, and she notes that it is Kagura. Naraku replaces Kagura with Byakuya, his final incarnation.
Souta is the little brother of Kagome Higurashi. He is a nice kid who cares a lot about his sister. Souta also thinks Inuyasha is cool.
Yuuji's mother. She can seem gentle but she's strong and very intelligent. Her husband, Kantarou, works outside the country. Chigusa remains ignorant of Shana's and Yuuji's true nature, but becomes a source of good advice for Shana on matters where Alastor can not counsel her. The Crimson Lord himself acknowledges and bows to her wisdom after a phone call between the two of them when he posed as Shana's guardian.
Age: 16 Sango is youkai slayer ("youkai taijiya") who hails from a village of professional y�kai slayers. The only member of Inuyasha's group to have no supernatural powers, Sango instead wields the Hiraikotsu, a massive boomerang made of y�kai bones, in addition to a broad repertoire of tools and tricks for battling y�kai. Sango is also a victim of Naraku's evil schemes; her family was killed and her entire village destroyed by Naraku's y�kai so that Naraku could then blame Inuyasha and manipulate Sango into trying to kill him. When that ploy failed, Naraku used a shard of the Shikon Jewel to revive and control her little brother Kohaku, forcing him to fight Inuyasha and company, and using him as a means by which to manipulate Sango. She seeks vengeance against Naraku, but her primary goal is to rescue Kohaku from Naraku's influence and somehow save his life, although currently it's uncertain if she will be able to do so as Kohaku's life is tied to the jewel shard. She has obvious feelings towards Miroku, although she is offended by his constant groping and lechery. ("Sango" means "coral")
Age: 18 A Buddhist "houshi," or low-ranking, itinerant monk, Miroku traveled the countryside performing services such as exorcisms and youkai exterminations to earn his living. He suffers from a hereditary curse originally inflicted upon his grandfather Miyatsu (also a Buddhist monk) by Naraku, who exploited Miyatsu's weakness for attractive women by taking the shape of one, and reflected one of Miyatsu's ofuda back to pierce the palm of his right hand (it appears to be his left hand in the English language manga where right and left are reversed). The hole in his hand became a kazana (air void or "wind tunnel") which sucks in anything not nailed down, regardless of mass. Miroku uses the kazana as a powerful weapon against youkai, but as he grows older, the kazana grows inevitably larger, and if the curse is not broken by Naraku's death, it will grow too large to control and consume Miroku himself—the same fate his grandfather and his father have already met. Probably as a result of this, Miroku takes a hedonistic approach to life which is uncharacteristic of a proper monk; he is a talented con artist who does not hesitate to invent fictitious supernatural menaces which he can then offer to combat in return for food and shelter, and like his grandfather he has a distinct weakness for pretty women. He makes a point of asking every attractive woman he meets if she will bear his child, claiming that he wants to be sure of an heir to continue his pursuit of Naraku if he dies, and his hands have a seemingly uncontrollable habit of wandering—something which often gets him soundly thumped by Sango, the favorite subject of his groping; however, in spite of his less-than-saintly behavior, Miroku proves to have a core of deep spirituality and, as a result, impressive spiritual powers. ("Miroku" is Japanese for Maitreya.)