Kyosuke Kiriya

Kyosuke Kiriya (桐矢 京介) briefly transformed into what was called Transformed Kyosuke (京介変身体) by the Hibiki production crew. In the stage shows, this form is dubbed Kamen Rider Kyoki (仮面ライダー強鬼) which means "Strong Demon". Kyosuke only transformed in the final episode of Kamen Rider Hibiki.

Kyosuke Kiriya
Kyosuke Kiriya is a young man attending the same school as Asumu Adachi and Akira Amami. He appears in the second half of the series wanting to be an Oni. Kyosuke is very strict and competitive, often correcting others of small mistakes (e.g. Asumu's notes) and getting himself and others in competitions that they don't want to do.

His reason for wanting to become an Oni was because of his estranged father. Only seeing what his father did in life, Kyosuke saw becoming an Oni as his chance to be greater than his father. Kyosuke pursued Hibiki, aiming to become his disciple. Hibiki saw Kyosuke's reason as selfish and refused to let him become his student but Kyosuke was adamant. Later, he formed a partnership with Asumu and pledged Hibiki to become his students.

After Akira persuaded Hibiki to let Asumu and Kyosuke become his students, he took them under his wing. However, Kyosuke struggled in nearly every training session, unlike Asumu. During the Orochi Sealing, Kyosuke aided Hibiki when the latter dropped his drumsticks. A year later, he is still apprenticed to Hibiki but is already allowed to transform. He fought the Makamou who kidnapped Hitomi Mochida in that form but was almost defeated until Ibuki and Todoroki came.

Trivia

 * Kyosuke is portrayed by Yuichi Nakamura, who would later go on to portray Yuto Sakurai in Kamen Rider Den-O.
 * Kiriya is a somewhat hated character, as it seems to reason that Kyosuke exists primarily to pursue a tiresome and one-sided rivalry with Asumu, and having pulled dishonest deeds. Fans were enraged when he becomes an Oni and Asumu does not. This flame was fanned higher when the production team later confirmed that both of them were supposed to have become Oni, but it was ultimately decided that Asumu would not, and Asumu's Oni suit was scrapped for parts to enhance Kiriya's Oni suit.