Midoriko was an exceptionally powerful priestess whose spiritual strength surpassed that of any living person. Legends claimed she could purify and annihilate ten demons simultaneously.
During one battle, after seven days and nights of relentless combat, she understood that victory was beyond her grasp. Her ultimate adversary was a creature formed from numerous demons fused with an evil human heart.
Realizing defeat was imminent, Midoriko allowed herself to be pulled into the creature's body. She seized its spirit and bound it with her own, resulting in the deaths of both and the creation of the Shikon Jewel. This jewel encapsulated her soul along with those of the demons she had entrapped.
The souls within the jewel are perpetually at war, which is why the Jewel’s power fluctuates depending on who possesses it.
Midoriko’s mummified remains were discovered in the exterminator village.
In the anime, there are hints suggesting Kirara fought alongside Midoriko, whereas the manga offers no such indications.
(Source: Inuyasha-Fan.com)
