Naka-Oni

The Naka-Oni is a fictional character in the manga series of Shaman King. It was created by Kyōyama Anna's uncontrolable Reishi(霊視) powers.

Osorezan Revoir
It was created when Kyōyama Anna and Asakura Yoh whent to a temple at new years day. When the prayers, hopes and worries exceeded 108, something that easily happened during that time and place, Anna's Reishi powers went out of control and created the Nakaoni.

While fighting with Matamune, when Anna's powers went way out of control, it began gathering the surrounding Onis in the area. The Onis began devouring each other and in the end, the Naka-Oni would evolve into an Oh-Oni.