In modern-day Tokyo, Kagome Higurashi lives on the grounds of her family’s Shinto shrine with her mother, grandfather and younger brother, Sota. On her fifteenth birthday, when she goes to retrieve her cat, Kagome is dragged into the enshrined Bone Eater’s Well (骨喰いの井戸 Honekui no Ido) by a centipede demon that emerged from it. But rather than hit the bottom, Kagome finds herself in the past during Japan’s Sengoku period. The demon is revealed to have originally been defeated fifty years prior by Kikyo, a warrior priestess who is the keeper of the Shikon Jewel (四魂の玉 Shikon no Tama, lit. “The Jewel of Four Souls”), an artifact created by the sacrifice of the priestess Midoriko which grants its holder’s desires. As pointed out by Kikyo’s younger sister, Kaede, Kagome is revealed to be the reincarnation of the now-dead Kikyo, who was the priestess in charge of looking after the sacred jewel. The Shikon Jewel was burned along with Kikyo’s remains to cast it out of this world entirely, in order to keep it safe from the hands of those who would abuse it. Then Kagome comes across a boy pinned by a sacred arrow on a tree, learning he is Inuyasha, a half dog-demon (yōkai), whom Kikyo trapped as her final act when he attempted to steal the jewel. Kagome frees Inuyasha to kill the centipede demon, but Kaede subdues him with a magical beaded necklace to keep him in line with Kagome saying “sit” or “sit, boy”, which causes him to violently crash to the ground. The Shikon Jewel was extracted from Kagome’s body by Mistress Centipede, and then later taken by a crow demon, which Kagome destroyed with her arrow, but in doing so, shattered the jewel into many shards that flew across Japan and into the possession of those who gain the individual shards’ power.
After Inuyasha gains his father’s sword Tetsusaiga, placing him at odds with his older half-brother Sesshomaru, he aids Kagome in collecting the shards and dealing with the threats they cause as they are joined by Shippo the young fox demon. Kikyo is partially revived while revealed to have been Inuyasha’s lover, but her version of how their falling out occurred brings the events into question. It was when the group is joined by the perverted monk Miroku, whose hand is cursed with a wind tunnel that was passed on to him from his grandfather, that his family’s curse and the events which resulted in Inuyasha’s imprisonment and Kikyo’s death were caused by the evil half spider-demon Naraku. The evolving Naraku is revealed to have been born from the soul of the evil bandit Onigumo inhabiting a body created by countless demons as part of a pact to acquire the Shikon Jewel for his own ends, seeking out the shard while absorbing demons to increase his power and remove any weaknesses. Inuyasha’s group is soon joined after by the demon slayer Sango and her two-tailed demon-cat Kirara. Sango’s clan was killed when her younger brother Kohaku fell under Naraku’s control and is kept alive by a Jewel shard. Over time, Inuyasha enhances Tetsusaiga into stronger forms while contends with Naraku’s minion incarnations like Kagura and Kanna, and the reanimated Band of Seven. Inuyasha’s team is loosely allied by Sesshomaru who took the orphaned girl Rin as a ward, the resurrected Kikyo, and Koga, the leader of the eastern wolf-demon tribe who seeks to avenge many of his comrades’ deaths and has a one-sided crush on Kagome.