The Lion Lord, Xeon claims to be the most powerful man in Celestia. He has the strength of ten thousand men and is a master of his sword, Vajrayaksa. In the past, it is hinted that he was a former prince that was engaged to be married to Hime. He was also the close friend of Youji, Hime's former sword instructor.
Both Hime and Xeon fought in the capital of New Celestia recently. Hime was able to defeat Xeon after releasing her Hitenoubu, regardless, Hime could not deliver the killing blow and Xeon was gravely wounded by the Queen when Agito interrupted.