Mibu Kyoushirou's personality is almost a direct opposite of the series' main character, Demon Eyes Kyou. Awkward and funny at the beginning of the adventure, Mibu Kyoushirou is, in fact, a frightening combatant called "the Demon-God" who is the only one to have beaten Kyou. Kyoushirou has the ability to transfer human souls. He uses this to transfer Kyou's soul into his own body while hiding Kyou's body. He killed many people in the past, including the brother of Shiina Yuya, Shiina Nozomu. He is actually a high ranked Mibu and is gifted in the handling of a sword and is thought to be the best swordsman of the clan to date. He knows the techniques of the Mumyou Jinpu Ryuu and is also the former owner of the Shibien. As far as areas of comparison go, his skill and potential rank him equal to Kyo and just below the former Crimson King.
His only wish is to protect Sakuya, whom he is in love with along with Kyou before the battle of Sekigahara. It is seen in the manga that he had always been in love with Sakuya and Kyou is a dear, close friend who cares for them both. He cares greatly for Yuya and would do anything to protect her, saying he will not let Kyou have her. Also, it is noted by Sasuke how Kyoushirou looks at Yuya tenderly as seen in Chapter 234.
Mibu Kyoushirou is one of the Red Cross Knights, created from the flesh and blood of the former Aka no Ou. He was a killing machine, but he had a very friendly heart, he only became friendly with Sakuya's influence. He was also a master of Mumyo Jinpu Ryuu Satsujin Ken. He once wielded the Shibien, one of Muramasa's Devil Swords, and killed many people with it until the sword turned black in color because it absorbed too much blood.
In the end of the manga it is shown that Kyoushirou is living with Sakuya and visits Yuya and Kyou.