Kaiko  

, 芥瑚

Kaiko is a female youma that serves as the protector of the Kirin. She possesses feathered wings, fur, and bird feet in appearance. In her debut, she was summoned by Keiki when he and Youko Nakajima were trapped on their school's roof by kochou. Kaiko carried the Suiguutou for Youko to wield against monsters, but due to Youko's lack of ability with a sword and the urgent need to escape, the group fled to the seashore. After defeating their pursuers, Keiki assigned Kaiko and Hyouki to safeguard and transport Youko to the Twelve Kingdoms while he departed with Hankyo. Upon arrival, they were separated from Youko and Jouyuu and sealed by Kourin, who had captured Keiki for her master. She was liberated after Youko reunited with Keiki and the Kirin was released from his spell.