Twenty-two years after the disappearance of his father, Wataru Kurenai lives in an infamous "haunted house" where he is destined as Kamen Rider Kiva to fight life-draining monsters called Fangires, the very race his father fought years ago before his disappearance. Wataru must also deal with Kamen Rider Ixa who is part of an organization seeking to destroy the Fangire menace, as well as the Fangires' own Rider, Kamen Rider Saga. The story is split between the actions of Wataru in the present (2008) and his father Otoya in the past (1986), slowly revealing the link between the Fangire Race and Kiva.
- Main article: List of Kamen Rider Kiva characters
The characters of Kamen Rider Kiva are spread throughout two time periods, each related to one another. There are the actions of Otoya Kurenai and the Fangire Hunter Yuri Aso with the Wolfen Jiro in the year 1986 with the first Ixa Ver.I that result in the various Fangires that persist to the current day, in 2008, with Otoya's son Wataru (as Kamen Rider Kiva) along and Keisuke Nago (as Kamen Rider Ixa Ver.X) and Yuri's daughter Megumi (also a Fangire Hunter), dealing with the Fangires to prevent deaths.
- Main article: Fangire
The Fangires (ファンガイア, Fangaia?) are stained glass-based vampires who feed off of the Life Energy (ライフエナジー, Raifu Enajī?) of humans to survive, with which they can disguise themselves as humans. Because of this, aware humans have formed a group to hunt the Fangires. Though Kiva usually captures a Fangire's soul to feed to Castle Doran, Fangires can be completely destroyed when shattered as seen by Ixa and stronger Fangires.
- Main article: List of Kamen Rider Kiva episodes
King of the Castle in the Demon WorldEdit
- Main article: Kamen Rider Kiva: King of the Castle in the Demon World
Movie Edition: Kamen Rider Kiva: King of the Castle in the Demon World (劇場版 仮面ライダーキバ 魔界城の王, Gekijōban Kamen Raidā Kiba Makaijō no Ō?) opened in Japanese theaters on August 9, 2008. It will feature two new Riders who have been shown in silhouettes in Japanese children's magazines, Kamen Rider Rey (仮面ライダーレイ, Kamen Raidā Rei?), who is a monster hunter named Takato Shiramine (白峰 天斗, Shiramine Takato?) played by Shouma Yamamoto (山本 匠馬, Yamamoto Shōma?), partnered to Rey Kivat (レイキバット, Reikibatto?, voiced by Norio Wakamoto) and the villain of the movie Takashi Sugimura (杉村 隆, Sugimura Takashi?), a death-row inmate who transforms into Kamen Rider Arc (仮面ライダーアーク, Kamen Raidā Āku?) with Arc Kivat (アークキバット, Āku Kibatto?, voiced by Norio Wakamoto), portrayed by Ken Horiuchi of the comedy troupe Neptune.