Rainbow Pearls

The were seven powerful multicolored pearl-sized artifacts with immense Yōki.

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 in episode 2:


 * (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: This ability first activated when Towa's Silver Rainbow Pearl transported her to the modern era when she was a toddler. Years later, another portal to the modern era transported Setsuna, Moroha, and Mistress Three-Eyes. After defeating Mistress Three-Eyes, the pearls of the three heroines facilitated their return to the feudal era.
 * Amplifying demonic power: When Mistress Three-Eyes consumed the Red and Golden Rainbow Pearls, it greatly enhanced her offensive and defensive capabilities.
 * Activating the energy blade of Kikujūmonji: Using the Silver Rainbow Pearl, Towa can fully use the powers of Kikujūmonji, and form a blade of pure energy that extends from the broken sword.
 * Exorcism of demonic energy: In cases demonic possession, the Silver Rainbow Pearl allows Towa to separate the demonic entity from the victim, and grants direct attack to the demon without harming the host.

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:
 * They are spheric jewels
 * They can enhance demonic power
 * The Golden and Silver pearls inside the right eye of Setsuna, and left eye of Towa, respectively, mirrors Inuyasha's right eye holding the Black Pearl that opened a portal to Border of the Afterlife that led to the tomb of Tōga.