Kyousuke Kiriya (桐矢 京介 Kiriya Kyōsuke) is Hibiki's newest student, who is training to become an Oni alongside Asumu. In the finale, Kyosuke briefly transformed into what was called Transformed Kyousuke (京介変身体 Kyōsuke Henshintai) by the Hibiki production crew.
In the stage shows, this form is dubbed Kamen Rider Kyoki (仮面ライダー強鬼 Kamen Raidā Kyōki, lit. "Masked Rider Strong Demon").
Kyousuke 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. Kyousuke 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, Kyousuke saw becoming an Oni as his chance to be greater than his father. Kyousuke pursued Hibiki, aiming to become his disciple. Hibiki saw Kyousuke's reason as selfish and refused to let him become his student but Kyousuke was adamant. Later, he formed a partnership with Asumu and pledged Hibiki to become his students.
After Akira persuaded Hibiki to let Asumu and Kyousuke become his students, he took them under his wing. However, Kyosuke struggled in nearly every training session, unlike Asumu, which shows that Kyousuke isn't very athletic. During the Orochi Sealing, Kyousuke 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.