Yasuda Yamada comes from a famous clan, the Kouiris Kiriou clan. He works there as a messenger and occupies a much more important role than that of some of the clan's swordsmen. He has a particular Japanese sword which does not cut like an ordinary weapon: its blade only cuts on the side.

Peaceful by nature, Yasuda hates violence and prefers to resolve conflicts without fighting. Through meditation, he developed a power called ドラゴンファイア (Dragon Fire), which means "Dragon Fire". This power represents his pure spirit and inner strength. It allows him to protect what is eternally precious to him, as well as the members of his clan, to whom he remains deeply loyal