If I succeed, I'll possess more demon energy than Master Kirinmaru.
When their enemy, the Great Dog General Tōga has been spotted in the land of Kamakura and was wounded from the battle with Ryūkotsusei, Kyūki and Konton reported it to Kirinmaru and suggested attacking him while he was injured. Kirinmaru furiously rebuked them, saying there was no honor in killing Tōga while he was weak as "a true battle must be one with honor and dignity". He instead summoned Riku and ordered him to gather medicinal herbs to heal Tōga. After Riku left, Kirinmaru said that the battle is meaningless unless both sides are willing to their all for victory, as he left they heard Zero chuckled as she said he could only learn the meaning of compromise and his rigid thinking is why they haven't ruled the western land yet.
Through Yotsume, Kyūki spied on Towa Higurashi, Setsuna, and Moroha. She recognized Moroha as the one who killed Tōkotsu, and asked Yotsume what Jakotsumaru was up to. Yotsume responded that he was busy gathering the bones needed to revive his father, so Kyūki told him to inform Jakotsumaru about the trio.
Following Tokōtsu's demise at the hands of Sesshōmaru's daughters and Jakotsumaru's demise at the hands of Inuyasha's daughter, Kyūki reported it to Kirinmaru, before assuring him that she will deal with them. Kyūki sent Yotsume to retrieve the rainbow pearl from Towa while she sent Fubuki after Moroha and Setsuna's rainbow pearls. Together with the purple rainbow pearl in her possession, Kyūki believed that with four rainbow pearls she could have more demon energy than Kirinmaru.
When Fubuki is eventually killed, and Yotsume was forced to retreat and flew to her mountain hideout, she stopped him from entering her lair with a barrier, and yelled at him for leading the half demon princesses to her. She let Yotsume borrow her purple rainbow pearl to fight them. Though Yotsume defeated Moroha, Towa and Takechiyo, he was easily killed by Setsuna.
Upon Yotsume's demise, the pearl returned to Kyūki's hand. She observed the dreams that the rainbow pearl had allowed her to access, and noted that it was jumbled, but she could make sense of it. The half demon princesses entered Kyūki's lair to confront her, but it was soon revealed that Kyūki's rainbow pearl had sealed Moroha and Towa's demonic energy, leaving Setsuna the only one to fight her. Kyūki transformed into her true form, and fought Setsuna, absorbing Setsuna's attack with her rainbow pearl that she held in her mouth. Hiding, Towa and Moroha learned that Towa could absorb demonic energy to reactive the power of her Kikujūmonji.
Towa attacked Kyūki, and stabbed into the rainbow pearl, but Kyūki easily knocked her away and grabbed her sword. Feeling defeated, Towa managed to use the Sōryūha to defeat Kyūki, returning to her humanoid form. Weakened, Kyūki was confronted by Riku, who mocked her for losing. Kyūki cursed Riku and then died with her skin melting off.
At first glance, Kyūki appears to be loyal to her master Kirinmaru, In reality, she wishes to acquire enough power in order to overthrow him.
Demon Form: In her demon form, she took the appearance of the white saber-tooth cat with multiple horns on her legs, paws, heads and a pair of wings.
Human Form: In her human form, she is with white skin and purple stripes underneath her green eyes, forearms and shins, long wavy purple hair with part of it tied back, green eyes, pointed ears, a pair of small horns on her forehead, red fingernails and toenails, and a pair of white-feathered wings on her back.
Kyūki wears a sleeveless red kimono with orange animal-like stripes, a purple hadajuban undershirt, a purple beaded necklace with a bell at the center, jagged gray sode shoulder pads with golden rings round the end and matching kusazuri waist pads, a golden bracelet on her left wrist, a purple obi sash, and a large white sash down the center of her legs with black jagged stripes at the end.
Kyūki walks barefoot, similar to Moroha, and Inuyasha.
Powers and abilities
- Shapeshifting: Kyūki can transform into a giant tiger with horns and whip.
- Light whip: Kyūki can shoot a long line of purple energy from her fingertips that she can manipulate by moving her arm.
- Crystal Ball: Used to communicate with Yotsume.
- Purple Rainbow Pearl: She possessed it until Riku stole it.
- Kyūki is based on the qiongqi from chinese mythology.
- Kyūki has the same Light Whip like Sesshōmaru.