"I walk the path of supreme conquest, and it is power that will reveal the way for me."
Admist the conflicts of the brutal Sengoku Period, the title character and his companions encounter a sprawling cast of characters. Amongst them, some prove to be truly cunning opponents or darker allies.
All spoilers are unmarked. You Have Been Warned!
Franchise-wide
- Sesshomaru is Inuyasha's cunning older half-brother and heir to his late father's title as Lord of the Western Lands. Initially a cold-hearted demon supremacist, Sesshomaru attacks Inuyasha to claim their father's sword Tetsusaiga but when beaten back learns to value his own seemingly useless blade Tenseiga when it saves the life of the young girl Rin. Becoming something of an uneasy ally to Inuyasha and his party, Sesshomaru helps battle the villainous Naraku using both his power and brilliant battle tactics, at one point besting Naraku and deducing his foe's removal of his own heart to keep himself invulnerable. Forming a romantic bond to Naraku's incarnation Kagura, Sesshomaru learns love when he witnesses her death, swearing vengeance and helps destroy Naraku after saving Rin from him, destroying the vile half-demon's body for Kagome Higurashi to enter the Shikon Jewel and erase him from existence. Years later, Sesshomaru has children with Rin and brutally raises them to save their mother when she is cursed, putting all of their lives at risk to force them to become the warriors they need to be and even helping his rival Kirinmaru come to terms with his own shortcomings before allowing his adversary to die in peace.
- Sesshomaru's mother is a charming and pleasant Great Demon who was once the mate of the Great Dog Demon himself. Left with secrets by her former lover, Sesshomaru's mother guides her son to reclaim the true powers of his inheritance, playfully manipulating him through it while demonstrating a measure of concern for his well being. Secretly allying with Kirinmaru to stop the Grim Comet, she proceeds to use and guide her own granddaughters as well to their own victory, ultimately using everyone to save the world.
- Kikyo was once the priestess entrusted to guard the Shikon Jewel and lover of Inuyasha until Naraku tricked them into mistrusting each other and mortally wounded her in the process. Resurrected fifty years later, Kikyo nearly succeeds in convincing Inuyasha to join her in death before learning the truth of their past and sets about seeing the fractured Jewel restored to use its power to eliminate Naraku for good. When mortally wounded, she even manages to predict the emotional reaction of her own reincarnation, heroine Kagome Higurashi, to manipulate her into rescuing Kikyo; and later persuades a Jewel-corrupted boy into turning on Naraku and joining her in her quest. Only killed when she elects to save the life of another rather than purify Naraku, Kikyo nevertheless leaves the heroes the means to finally destroy their foe for good while she dies blissfully in her lover's arms.
- Kagura is the second incarnation of Naraku and an intelligent wind sorceress who lures the wolf demon tribe into a trap to slaughter them, soon after revealing she is reluctantly forced into Naraku's service by him holding her heart. Seeking to free herself, Kagura regularly attempts to pit Naraku against his enemies, including trying to both protect the demon Sesshomaru and lure him into bringing about Naraku's destruction, forming a subtle romantic bond with him. Kagura also assists Naraku's detachment, the Infant with his schemes before being subordinated to the monstrous Hakudoshi, but is able to get the last laugh by tearing him apart when she knows Naraku will no longer defend him from Inuyasha's team. Finally poisoned by Naraku, Kagura spends her final moments with Sesshomaru, accepting her end with dignity and even happiness as she notes she is the "free wind" at last.
- Bankotsu, leader of the Band of Seven, is an affluent young man and brutal mercenary who was executed fifteen years prior to the events of the series. Revived by Naraku with his followers, Bankotsu promptly massacres the lord who betrayed him for revenge and to retrieve his weapon, the Banryu, christening it by making the lord his thousandth kill. Setting about to his missions, Bankotsu proves that despite his lack of formal education, he is an incredibly intelligent fighter and strategist who simply believes in following his own bloody path. Upon the betrayal of his ally Renkotsu, Bankotsu manipulates him into a false sense of security before killing him to remove his Shikon Jewel shards and face Inuyasha in a battle to either win or die on his own terms where he accepts his defeat and final end with his characteristic good humor.
- Byakuya of the Dreams is the friendly and playful yet cunning final incarnation and right-hand of Naraku. With his abilities Byakuya provides reconnaissance for his father, as well as manipulating an attack on a wolf demon tribe and luring Inuyasha and Sesshomaru into battling each other for Naraku's goals. In his final outing, Byakuya collects a power to enact Naraku's final scheme—pointedly sparing an innocent who has nothing to do with his task along the way—and while playing out his role, calmly leaves himself open to attack, commenting he dies with no regrets, fading away having played his part perfectly.
Yashahime: Princess Half-Demon
- Kirinmaru, Beast Lord of the Eastern Lands, is a mighty Great Demon who conquered all he surveyed and defeated every opponent until his clash with the Great Dog Demon. A ruthless, but honorable man, Kirinmaru allied with the Great Dog Demon to stop the apocalyptic Grim Comet and planned to save his sick daughter Rion. Later allying with the Great Dog Demon's son, Sesshomaru, for his own plans and to stop the comet's resurgence, Kirinmaru sends a piece of himself to the future as "Mr. Osamu Kirin" to ensure his victory, in a grand gambit that will see him hailed as the savior of the world entire. Despite his seeming elitism and immense pride, Kirinmaru shows nothing but respect to the half-demon princesses who challenge him, acknowledging and respecting their strength, while being seen by even the taciturn Sesshomaru as a truly worthy adversary.
- Riku is an unfailingly polite, upbeat "pirate" and detachment of Kirinmaru's who is constantly switching loyalties and goals in his quest to help others in his own unique ways. A servant to Kirinmaru who grew attached to the true self of Zero before she tore out her emotions to create the Rainbow Pearls, Riku takes his time in slowly collecting all seven of the Pearls from across the lands, manipulating the Four Perils into conflicts with Towa and her friends so that Riku can swoop in and claim Rainbow Pearls from the Perils' fallen bodies. Though succeeding in his plot to restore the Pearls to Zero, Riku changes tactics after Zero's death, deciding to become a "bodyguard" to Towa and the half-demon princesses, protecting them from a number of threats. Soon enough allying with Rion, Riku works with her to discover and sabotage several of Kirinmaru's plans, Riku ultimately being the one to orchestrate the insane Kirin's death by sacrificing himself as a distraction. Surviving his apparent death, Riku once more allies with Towa and her gang to become demon hunters and protectors of all the land.
- The Spirit of the Tree of Ages takes the form of Kikyo to interact with the half-demon princesses. Telling them of the threat Kirinmaru poses but pointedly leaving out the full story, the Spirit uses the heroines to subvert Kirinmaru's plot to bring the Grim Comet to Earth. Even when Kirinmaru seemingly succeeds, the Spirit ensures the princesses have the means to travel through time, saving both their mother Rin and the whole world as per the Spirit's plot with Sesshomaru, risking the girls' lives to save everyone.
