Rainbow Pearls

The were  seven powerful multi-coloured pearl-sized artifacts which grants immense power to whoever possesses it.

Description
These pearls appear to be in multiple colors, hence why they are referred as "Rainbow pearls". There were at least three pearls confirmed to exist:


 * (inside the left eye of Towa);
 * (carried by Moroha, originally Tōkotsu);
 * (inside the right eye of Setsuna);
 * (on the left ear of Riku);
 * (in possession of Kyūki);
 * (on the left ear of Riku);
 * (in possession of Kyūki);

Effects



 * Opening time portal
 * The first time this ability activated was when Towa's Silver Rainbow Pearl transported her when she was younger. The second time was when Setsuna, Mistress Three-Eyes and Moroha came when they were all fighting eachother.
 * All four of them came through and landed in front of the sacred tree. However during Setsuna and Moroha's trip through, they were severely weakened (unabled to move or even lift up their heads) while Mistress Three-Eyes seemed completely unharmed.
 * Greatly increasing the powers of demons (As the Sacred Jewel did before it disappeared in the original series)
 * Mistress Three-Eyes stole the Red and Golden Rainbow Pearls which made her much more dangerous before being killed by Setsuna.
 * Summoning the blade
 * After Mistress Three-Eyes breaks the blade of Kikujūmonji, Towa's Silver Rainbow Pearl activates her powers.
 * Defeats an enemy

Warring States Era
Some time in their childhood, mostly possible in their infancy, Towa and Setsuna had two Rainbow Pearls - silver and golden respectively - placed into each one of their eyes, possibly by their father Sesshōmaru. And for Moroha's part, she had her red pearl given to her via lip-makeup pouch by her parents - Inuyasha and Kagome.

Towa and Setsuna, at the age of four, were separated from each other during a forest fire. While desperately searching for her younger sister, Towa's silver Rainbow Pearl opened a a time portal that sucked into and sent her into present-day Japan, where she is found and raised by Kagome Higurashi's younger brother, Sōta, and his family.

Throughout the Series
After ten years of their separation, Towa had been living in the present with the Higurashi family and Setsuna in the past with the Demon slayers respectively.

Back in the past, the Demon Slayers Hisui, Kohaku and Setsuna corner Moroha, mistaking her for a demon that is attacking the locals, until the real culprit - Mistress Three-Eyes appears and steals the red and gold Rainbow Pearls in Moroha and Setsuna's possession.

Suddenly, a portal opens, dragging Setsuna, Moroha, and the Mistress Three-Eyes to the present before Towa, who recognizes her long-lost beloved twin sister. Sensing the silver Rainbow Pearl in Towa's possession, Mistress Three-Eyes attacks her as well. Towa's sword breaks when she tries to slash Mistress Three-Eyes because it was ordinary, much to Towa's shock, but Towa manages to use the Silver Rainbow Pearl's power to convert the remains into a laser blade and damage Mistress Three-Eyes. Setsuna finishes her off with her weapon and she and Moroha recover their Rainbow Pearls.

Trivia

 * The Rainbow Pearls share similarities with the Sacred Jewel:
 * Both are sphere shaped jewels;
 * Both are pursued by many demons and can make them stronger;
 * The Golden Rainbow Pearl in Setsuna's right eye is similar to her uncle Inuyasha's right eye carrying the Black Pearl to open a gateway to the Border of the Afterlife where her grandfather's tomb is.