Jienda is a seahorse-like Yin-Self Horror and one of the nine Horrors freed from the slate that uses their malice to seal the legendary Horror Eyrith. Being the only surviving Ady Slate Horror, Jienda became the final host of Eyrith's seed.
Jienda is freed from the Ady Slate when a mysterious person destroys the slate using a Madou Art technique. The last of the Ady Slate Horrors, Jienda is a Horror with an eye for a right hand. Jienda possesses the body of a young lady. However, she is soon found by Eiji Busujima, who easily knocked her out so that he can extract the seed from the Ady Slate Horror when she congregates back into a stone.
In the series, Jienda is the final of the nine Horrors used as the foundation to seal Eyrith in the Ady Slate to be captured, and the final carrier of Eyrith's seed.