As a child, Seimei already had the ability of seeing spirits. Because of that, people were afraid of him and said he was born from a fox.

He learned from his master Tadayuki and became a very gifted onmyouji, feared by demons. He lives alone with spirits and fairy objects that serves him.

Seimei is a very cultivated man who also likes jokes, especially to the detriment of Hiromasa.