Kamen Rider Hibiki

Takeshi (猛士) is a secret organization based in Yoshino, Nara, having been established two centuries ago as a partnership between the Oni and a select group of humans to defend Japan from the Makamou. In the present day, Takeshi has offices across Japan composed of Oni and a backup team that provided intelligence and support.

The combatant agents of Takeshi are known as Oni, who have long protected humans from the Makamou for centuries. The title of every Oni bears the -ki suffix (鬼), which is semantically identical to "Oni" in Japanese language. It also has some resemblance with the real name of the Oni.

While transformed, each Oni equips with three types of respective Ongekitai (音撃帯) utility belt to be compatible with their personal Ongeki Weapons (音撃兵器, Ongeki Heiki) for the finishing moves:

• Ongekiko (音撃鼓, Ongekikō) can only be used by Percussion instrument user Oni.
• Ongekimei (音撃鳴) can only be used by Wind instrument user Oni.
• Ongekishin (音撃震) can only be used by String instrument user Oni.

Hibiki (ヒビキ)

Real name Hitoshi Hidaka (日高 仁志, Hidaka Hitoshi), Hibiki is among the most seasoned Oni with a strong sense of ethics and believes in constantly training oneself to keep up with their strength while being somewhat of a mentor figure. He takes Asumu under his wing, helping in any way that includes giving him needed advice. Using the Transformation Tuning Fork Onkaku (変身音叉・音角, Henshin Onsa Onkaku), he transforms into Kamen Rider Hibiki and use his Ongekibou Rekka (音撃棒・烈火, Ongekibō Rekka) drumsticks as bludgeoning weapons. He later acquires the ability to become Hibiki Kurenai (響鬼紅) from his summoning training, and then Armed Hibiki (装甲（アームド）響鬼, Āmudo Hibiki/Hibiki Sōkō) with a modified ancient vocal weapon known as the Armed Saber (装甲声刃（アームドセイバー）, Āmudo Seibā).

Ibuki (イブキ)

Real name Iori Izumi (和泉 伊織, Izumi Iori), he is a composed member of an Oni family that oversee Takeshi's Yoshino headquarters and takes that position of protecting others and taking extremely dangerous missions with pride. But Ibuki gradually begins fearing death while realizing he was not as strong as he assumed himself to be, though he musters the courage to help Hibiki during the Orochi event. Using the Transformation Oni Whistle Onteki (変身鬼笛・音笛, Henshin Onibue Onteki), he can transform into Kamen Rider Ibuki (仮面ライダー威吹鬼, Kamen Raidā Ibuki) and use his Ongekikan Reppu (音撃管・烈風, Ongekikan Reppū) trumpet gun as a weapon.

Akira Amami (天美 あきら, Amami Akira)

Ibuki's apprentice, who wanted to become an Oni out of revenge after her parents were killed by Makamou. While able to become an Oni, she eventually gives up her goal of being an Oni following her time with Shuki and resumes a normal life.

Todoroki (トドロキ)

Real name Tomizo Todayama (戸田山 登己蔵, Todayama Tomizō), he was originally an apprentice to Zanki who resolved to make a name for himself as the present-day Kamen Rider Todoroki (仮面ライダー轟鬼, Kamen Raidā Todoroki) rather than inherit his master's title. To transform, Todoroki uses the Transformation Oni String Onjo (変身鬼弦・音錠, Henshin Kigen Onjō) bracelet. After becoming an official Oni, Todoroki is given his mentor's Ongekigen Retsurai (音撃弦・烈雷) guitar for his own.

Zanki (ザンキ)

Real name Zaoumaru Zaitsuhara (財津原 蔵王丸, Zaitsuhara Zaōmaru), he is among the most seasoned of the Oni with Todoroki as his apprentice. Using the Transformation Oni String Onka (変身鬼弦・音伽, Henshin Kigen Onka) bracelet, he can transform into Kamen Rider Zanki (仮面ライダー斬鬼, Kamen Raidā Zanki) and uses his OngekiShingen Retsuzan (音撃真弦・烈斬) guitar as his weapon. Due to an injury he suffered from mentor Shuki during his days as her apprentice, Zanki resolves to serve as Todoroki's support while his apprentice takes over his duties as an Oni. While he ended up dead when forced to transform again, he uses a forbidden spell Shuki taught him to remain among the living until Todoroki is able to stand on his own two feet.

Ichiro Tachibana (立花 勢地郎, Tachibana Ichirō)

The current head official of Takeshi's Kantō branch and father of the Tachibana sisters, a cheerful man who gives the Oni under him thoughtful advice while sending them out on their missions while having a personal library where he researches the Makamou.

Kasumi Tachibana (立花 香須実, Tachibana Kasumi)

The eldest Tachibana sister, a very intelligent individual who usually acts as a field support by providing the Oni supplies and extra Disc Animals.

Hinaka Tachibana (立花 日菜佳, Tachibana Hinaka)

The youngest Tachibana sister, a cheerful girl who usually hangs around Takeshi Headquarters to track the Makamou and rarely goes out into the field.

Midori Takizawa (滝澤 みどり, Takizawa Midori)

Takeshi's equipment and weapons designer. She is responsible for creating the sound weapons for the Oni and the Disc Animals. She is an old friend of Hitoshi, who has been friends since childhood and joined Takeshi to aid him once he became the current Hibiki.

Konosuke Kogure (小暮 耕之助, Kogure Kōnosuke)

The head of Takeshi's weapon design section and Midori's mentor, a former Oni who is said to have defeated twenty Makamou single-handedly. He is also a singer in his spare time. Much of Takeshi, including Ichiro, fears him because of his strict disciplinary personality (with the exception of a few people). When he is angered, he chases his "victim" and hits them with a paddle. He also travels using a motorcycle with the newly improved Armed Saber which he made and was almost too powerful for any Oni to control, causing them to lose their transformation abilities for a month. When Torodoki and Hibiki were affected by the Armed Saber, Konosuke trained the two with his special training to improve their powers. The training, utilizing energy from the gut while singing, paid off for Hibiki because it enabled him to wield the Armed Saber. After that, Konosuke left for Yoshino.

Asumu Adachi (安達 明日夢, Adachi Asumu)

A high school student who Hibiki took under his wing for advice and decides to become his apprentice before resolving to live a normal life and support Hibiki instead.

Hitomi Mochida (持田 ひとみ, Mochida Hitomi)

Asumu's classmate and Todoroki's cousin.

Kyosuke Kiriya (桐矢 京介, Kiriya Kyōsuke)

A high school student who becomes Asumu's rival after becoming an apprentice to Hibiki. After Asumu stepped down from becoming an Oni, Kyosuke became both Hibiki's only apprentice and a full-fledged Oni a year after the events of Orochi.

Ikuko Adachi (安達 郁子, Adachi Ikuko)

Asumu's mother who works as a taxi driver.

Shuki (シュキ)

Real name Shiori Shinagawa (品川 栞, Shinagawa Shiori), Shuki is a former Oni with a knowledge of Oni lore who uses ancient Oni techniques that include the Firebird shikigami and means to appear in her early 30s. Unlike the other Oni who fight the Makamou to protect humans, Shuki's motivation was to track down and kill the Makamou Notsugo after it slaughtered her family years ago. Because of her personal vendetta, and inflicting her former apprentice Zanki with a crippling injury when her chance to kill Notsugo presented itself, Shuki was stripped of her Oni title as she was being gradually consumed by her Oni power. Shuki resurfaced years later in a suit of Oni Armor (鬼の鎧, Oni no Yoroi) before stealing Todoroki's Onjo to resume her form as Kamen Rider Shuki (仮面ライダー朱鬼, Kamen Raidā Shuki), taking Akira as her apprentice due to their similarities. Shuki succeeds in exacting her revenge on Natsugo by sacrificing herself so Zanki can kill it, and Shuki requesting Zanki to bury her under flowers to conceal her true face.

Among making many changes to the Kamen Rider look, Kamen Rider Hibiki introduced Kamen Rider Shuki, the third officially recognized female Heisei Kamen Rider in a Kamen Rider series after Kamen Rider Femme from Kamen Rider Ryuki and Kamen Rider Larc from Kamen Rider Blade.

The term used for a pair of homunculi servants that aid a Makamou, revealed to be clones created by a couple known as the "Man and Woman of the Western-Style House" (洋館の男女, Yōkan no Danjo), who are the antagonists of most of the series despite preferring to act from behind the scenes. It is assumed they were humans who achieved a means of immortality long ago and have been modifying the Makamou to wipe out the Oni and destroy humanity. The Douji (童子, Dōji) are the clones of the Man while the Hime (姫) are clones of the Woman, the Parent clones who care for the Makamou having swapped voices and the ability to transform into humanoid versions of their "children". The Parents are created by Kugutsu (クグツ) clones, the ones in black trench coats creating the Giant-Type Makamou Parents with the black Kugutsu Hime providing them with armor modification, while the ones in white robes create the Summer-Type Makamou Parents. The Kugutsu were executed by Super Douji and Super Hime. Eventually, the Man and Woman are forced into a ceasefire with the Oni as the Makamou were becoming too uncontrollable during the Orochi Phenomenon. A year after the Orochi Phenomenon was stopped, they created the Makamou Satori to abduct an ideal human (Hitomi) so they can use her to create more stable clones. At the end of the series, they are revealed to be the clones of the "Mysterious Man and Woman" (謎の男女, Nazo no Danjo), who still need them to carry on their work.

Super Douji (スーパー童子, Sūpā Dōji) and Super Hime (スーパー姫, Sūpā Hime)

The "perfected" version of the Douji and Hime clones that replace the obsolete clones in supporting Makamou, originally childish in personality before they "matured" into homicidal psychopaths wanting to taste Oni blood. But they need to eat a special "armor orb" at a regular basis to prolong their lives. During the Orochi Phenomenon, the clones started to develop a sense of self as they begin, with Super Hime starting to question their existence and their creators' intent, to Super Douji's annoyance. After being told to protect the Oni, they attempted a rebellion against their creators' will which resulted in them dying from losing the method that prolonged their short lives.

The regular antagonists of the series; the Makamou (魔化魍, Makamō) are an assortment of monstrous creatures that usually dwell in the rural areas and consume human beings as food. Chimerical in appearance with their size and shape depending on the environment they are born in, and serving as the basis of the yōkai myths, the Makamo are a naturally created phenomena though some have been modified by the Man and Woman to be stronger and unpredictable. But the Makamou can destabilize and explode when exposed to pure sound produced by the Oni's attacks.

In the final arc, a chain of events called the Orochi Phenomenon (オロチ現象, Orochi Genshō) occurs. Marked by the appearance of Kodama's Forest, every known Makamou appears at the same time, increasing in massive numbers to the point where not even the Man and Woman can control them. By the climax, the Makamou start to dissolve into a purple miasma and killing by the hundreds. Hibiki eventually stopped Orochi by performing the sealing ritual, dealing with a massive army of Makamou bent on stopping him from ending their era before it could begin. In the end, the Orochi was halted and Makamou numbers dwindled back to normal.

Giant-Type Makamo

The most common type of Makamou, essentially daikaiju with heights that vary from 22 ft. to 75 ft. Makamou that fall under this listing include Tsuchigumo (ツチグモ) and Bakegani (バケガニ).

Summer-Type Makamou

Human-sized Makamou that normally appear during the summer, apparently starting the Japanese legend of ghosts and yōkai appearing on Earth during the summer. While the Summer-Type Makamou lack in size, they make it up in their ability to replicate themselves in large numbers and when one is destroyed they can easily be replaced. The key to destroying them is to destroy the original so no more replicates can be created. The Ongekida finishers are the most efficient way of destroying them.

Experimental-Type Makamou

Makamou developed by the Man and Woman to suppress the other two types, modified to be resistant to Oni attacks after the Man and Woman analyzed the Armed Saber.

Kodama (コダマ)

A treelike Makamou whose appearance marks the beginning of an Orochi event, able to traps its victims within a forest it spawns. Todoroki was dispatched to investigate, only to be ambushed by a wooden puppet Kodama created. The puppet managed to overpower Armed Hibiki and drive the Oni out of its forest. The Kodama later reappeared, trapping Ibuki and Kasumi, whom the monster intended to eat. While Ibuki and Todoroki battle the medium, Asumu and Kyosuke find Kodama and manage to free Kasumi from it, the medium feeling its master's pain before being quickly destroyed by Ibuki while Kodama is destroyed by Armed Hibiki.

• Konosuke Kogure (32, 33): Akira Fuse (布施 明, Fuse Akira)
• Shuki (36, 37): Reiko Kataoka (片岡 礼子, Kataoka Reiko)