Souji Tendou

Souji Tendou (天道 総司, Tendō Sōji), real name Souji Kusakabe (日下部 総司, Kusakabe Sōji), is a wild card and possessor of the Kabuto Zecter (カブトゼクター, Kabuto Zekutā), which he acquired on the day of the meteor along with the Rider Belt (ライダーベルト, Raidā Beruto) from a version of himself from an alternate future. This played in Souji having a sense that is meant for greatness that makes him initially appear arrogant but is very compassionate. He often seems to follow monk-like philosophies of peace, using the kanji in his full name to in his formal instruction: "The man walking the path of Heaven, and will rule everything." (天の道を行き、総べてを司る男, Ten no michi o Iki, Subete o Tsukasadoru otoko) or quoting amazingly appropriate zen-like phrases he supposedly learned from his grandmother. Having no job or college education despite being very talented, Souji normally stays home with Juka before becoming a regular customer at Bistro La Salle after meeting Hiyori Kusakabe, whom he recognizes as both the girl he saved and a Native Worm whom he considers his little sister. This played in his ability to recognize Worms in disguise merely fights for his own needs to wipe the aliens out and provoking ZECT as a result. After defeating the Worms and ZECT's corrupted higher ups, Souji leaves Japan to travel to France.

As Kamen Rider Kabuto, he is usually in his pupa-like armored Masked Form (マスクドフォーム, Masukudo Fōmu) before using the Kabuto Zecter's Cast Off (キャストオフ, Kyasuto Ofu) command to assume the sleeker and more combat-oriented Rider Form (ライダーフォーム, Raidā Fōmu) which uses the Clock Up (クロックアップ, Kurokku Appu) ability to travel at near-light speeds to match the speeds of the Worms or for Kabuto to perform his tachyon-powered Rider Kick (ライダーキック, Raidā Kikku) finisher. Both forms use the Kabuto Kunai Gun (カブトクナイガン, Kabuto Kunai Gan), a sidearm that has a Gun Mode (ガンモード, Gan Mōdo) for performing the Avalanche Shoot (アバランチシュート, Abaranchi Shūto) finisher, an Axe Mode (アックスモード, Akkusu Mōdo) for performing the Avalanche Break (アバランチブレイク, Abaranchi Bureiku) finisher, and a Kunai Mode (クナイモード, Kunai Mōdo) for performing the Avalanche Slash (アパランチスラッシュ, Abaranchi Surasshu) finisher, and the Kabuto Extender (カブトエクステンダー, Kabuto Ekusutendā), a modified Honda CBR1000RR able to change from Masked Mode (マスクドモード, Maskudo Mōdo) to Ex Mode (エクスモード, Ekusu Mōdo).

Kabuto later acquires the Hyper Zecter (ハイパーゼクター, Haipā Zekutā), a Zecter made by ZECT in the future, which enables him to assume Hyper Form (ハイパーフォーム, Haipā Fōmu) by using the Hyper Cast Off (ハイパーキャストオフ, Haipā Kyasuto Ofu) command. As a stronger version of Rider Form, Kabuto is capable of using the Hyper Clock Up (ハイパークロックアップ, Haipā Kurokku Appu) ability to move at great enough speeds to potentially travel seven years through time as well as to perform his Hyper Kick (ハイパーキック, Haipā Kikku) finisher. He also acquires the Perfect Zecter (パーフェクトゼクター, Pāfekuto Zekutā), which can switch between Sword Mode (ソードモード, Sōdo Mōdo) and Gun Mode. By increasing the Perfect Zecter's power with the TheBee, Drake, and Sasword Zecters, he can perform one of two finishers: Maximum Hyper Typhoon (マキシマムハイパータイフーン, Makishimamu Haipā Taifūn) via Sword Mode or Maximum Hyper Cyclone (マキシマムハイパーサイクロン, Makishimamu Haipā Saikuron) via Gun Mode.

Souji Tendou is portrayed by Hiro Mizushima (水嶋 ヒロ, Mizushima Hiro). As a child, Souji is portrayed by Sean Wiig (ショーン・ウィーグ, Shōn Wīgu).

Arata Kagami

Arata Kagami (加賀美 新, Kagami Arata) is the son of ZECT's leader Riku Kagami, unaware of the organization's true agenda while fighting for the betterment of humanity as Kamen Rider Gatack (仮面ライダーガタック, Kamen Raidā Gatakku). Having joined ZECT to avenge his younger brother Ryou Kagami, works with Hiyori at Bistro La Salle, Arata has a good heart but is impulsive often acts without thinking. In the previous timeline, Kagami married a Hiyori Kusakabe before helping Souji alter the timeline so the damage caused by the Worms' meteor would be minimized in Shibuya. In the new timeline, Arata meets Souji all over again when the latter claimed the Kabuto Zecter that he was to upon its completion. Being the only member of ZECT to know Souji's identity as Kabuto, momentarily using TheBee Zecter after Yaguruma was relieved of his duty, Arata became torn between his duty to ZECT and seeing Souji as a friend.

Arata eventually acquired the Gatack Zecter (ガタックゼクター, Gatakku Zekutā) and, becomes Gatack in the current timeline while learning the truth behind ZECT. They managed to wipe out most of the Worms before helping the rebels against the compromised ZECT led by Masato Mishima and the Native-class Worm leader Negishi. After ZECT was defeated, Arata started a new life with his father in the police force. During the events of Kamen Rider Zi-O, learning he is one of the few to remember ZECT and the Worms due to a time distortion, Arata helps the titular protagonist prevent a new Worm invasion while representing Souji.

As Kamen Rider Gatack, he is usually in his Masked Form equipped with the twin shoulder-mounted Gatack Vulcan (ガタックバルカン, Gatakku Barukan) cannons, which possess a shooting radius of 1 kilometer, before using the Gatack Zecter's Cast Off command to assume Rider Form where he gains access to the Clock Up ability and wields the twin Gatack Double Calibur (ガタックダブルカリバー, Gatakku Daburu Karibā) shotels, which consists of the gold-colored Plus Calibur (プラスカリバー, Purasu Karibā) and the silver-colored Minus Calibur (マイナスカリバー, Mainasu Karibā) that he can combine into a scissor-like weapon for his Rider Cutting (ライダーカッティング, Raidā Kattingu) finisher. Both forms use the Gatack Extender (ガタックエクステンダー, Gatakku Ekusutendā), a modified Honda XR250 Motard able to change from Masked Mode to Ex Mode. Gatack once acquired the Hyper Zecter to assume Hyper form in the DVD special Kamen Rider Kabuto Super Battle DVD: Birth! Gatack Hyper Form!!.

Arata Kagami is portrayed by Yuki Sato (佐藤 祐基, Satō Yūki).

Hiyori Kusakabe

Hiyori Kusakabe (日下部 ひより, Kusakabe Hiyori) is first shown as a co-worker of Kagami's at the Bistro la Salle. She was involved in the meteor crash seven years ago along with Tendou. Due to the accident, her parents were killed. She believed that they were murdered by a person wearing a Rider Belt, but after a period of uncertainty she concludes that Tendou, despite owning the belt, would never do something like that. After seeing Gatack wear another belt and discovering that he was Kagami, she also began to doubt him. In the end however, she decides to trust both of them as they have helped her so much. She carries a green crystal that originated from Area X, ground zero of the meteor crash. She seems to be able to talk with and read the emotions of inanimate objects, such as drawings and machines. She's quite clumsy and tends to zone out while working, resulting in complaints by customers. Through several mishaps and accidents, she was able to discover the identities of all the Riders besides Drake. Later in the series, it was discovered that Hiyori is the child of a Native Worm who impersonated Tendou's mother down to her pregnancy, and later gave birth to Sisyra Worm (シシーラワーム, Shishīra Wāmu). This technically makes her Tendou's younger sister. During episode 33, the energy charge from the Hyper Zecter sent her along with the Souji Kusakabe to the edge of time and space. The Hyper Zecter later appeared in the normal dimension, showing one of Hiyori's drawings to Tendou and Kagami.

She reappeared during episode 38, being led away by Kusakabe Souji, at the edge of time and space. She returns to the real world in episode 43 to defend Dark Kabuto from Hyper Kabuto, stating that she no longer desires to live in the human world. Ultimately however, after a compelling speech by Tendou saying that she will not be hated in the human world, even though she is a Worm, she abandons Kusakabe Souji and returns to the human world. However, she is then attacked by Dark Kabuto. After being saved by Tendou, she returns to an almost normal life, and begins making her own menu and dream of owning a restaurant come true. During the epilogue, she returns to her normal life in working at the Bistro la Salle, and now has Jyuka as a sister. As a human, she is 18 years old.

Hiyori Kusakabe is portrayed by Yui Satonaka (里中 唯, Satonaka Yui). As a child, Hiyori is portrayed by Reina Fujii (藤井 玲奈, Fujii Reina).

Jyuka Tendou

Jyuka Tendou (天道 樹花, Tendō Juka) is presented as Souji's younger sister, but in truth she seems to be his younger cousin. They were both taken in by their grandmother after the Shibuya meteorite crash. She's really close to Souji, who she calls "older brother", and tends to act the same way he does; such as talking about her grandmother and pointing to the sky. She was injured in a car crash caused by Kamishiro, but blows it off to her brother's concern. She also assists her brother in running noodle carts across town. She has different ways of saying "Good Morning" to Tendou and loves his cooking. Lately, she has been targeted by ZECT and the Worms. So far two Worms, disguised as Misaki and Daisuke, tried to either kidnap or kill her.

She seems to be aware of the Zecters as the Kabuto, TheBee, and Drake Zecters fly around the entire Tendou household, while the Sasword Zecter crawls on the dining table. It is unclear, however, whether she knows that Souji is a Kamen Rider. During the epilogue, it is shown that she has accepted Hiyori as her "sister" and is now working with her at the Bistro la Selle. 13 years old.

Jyuka Tendou is portrayed by Natsumi Okumura (奥村 夏未, Okumura Natsumi).

Yumiko Takemiya

Hiyori and Kagami's boss at the Bistro la Salle restaurant, Yumiko Takemiya (竹宮 弓子, Takemiya Yumiko) seems to tolerate Hiyori's clumsiness and Kagami's tardiness. She sometimes requests Tendou to be her cook as he is a usual customer. 36 years old.

Yumiko Takemiya is portrayed by Megumi Nishimuta (西牟田 恵, Nishimuta Megumi).

Daisuke Kazama

Daisuke Kazama (風間 大介, Kazama Daisuke) is a metro-sexual make-up artist who openly befriends women, seeing them as the treasure of life. His partner, a little girl named Gon, always follows him around, completing sentences for him since Daisuke seems to be in eloquent at times. Prior to his first appearance, he accidentally found the means to become Kamen Rider Drake (仮面ライダードレイク, Kamen Raidā Doreiku).

Daisuke Kazama is portrayed by Kazuki Kato (加藤 和樹, Katō Kazuki).

Gon

Real name: Yuriko Takayama (高山 百合子, Takayama Yuriko), Gon (ゴン) is a girl whom Daisuke has accompanied, she seems to have amnesia but at the beginning of episode 17, she slowly remembers time before she met Kazama Daisuke. Gon also pictures her mother Junko (順子), but cannot make out who it is. She always completes Kazama's sentences for him, usually after make-up sessions. She is incredibly mature for her age, often taking initiatives which surprise even Souji. In the end, after remembering her mother's face on the day that they were attacked at the bus by the same Worm that tried to kill her mother, she was finally reunited with her mother. Drake killed the Worm, and Gon completely remembered her past but unfortunately forgot about Daisuke and treated him as a complete stranger afterwards. However, she regained her memories of being Gon while reading an article on Daisuke in a teen magazine. She also helps Daisuke regain his Drake Zecter (ドレイクゼクター, Doreiku Zekutā) from his Worm imitation. She recently discovered the identities of the first five Riders, when they ganged up on Daisuke, who they believed was a Worm. In her latest appearance, she has given the Drake Grip to Souji after stealing it from Daisuke. She returns to help both Daisuke and Rena with the Hopper Riders by spraying them with a fire extinguisher; however, when Rena gains her Worm memories, she is attacked by Rena. During the epilogue, she is still working with Daisuke, although no longer wearing her trademark hat. She also insists that she now be called Yuriko, not Gon. 8 years old.

Gon is portrayed by Airu Kanzaki (神崎 愛瑠, Kanzaki Airu).

Tsurugi Kamishiro

Tsurugi Kamishiro (神代 剣, Kamishiro Tsurugi) is a descendant of the English nobility of the Discabil family, calling himself "the man who replaces the gods (Kamishiro) with a sword's slash (Tsurugi)" in his introductions. He is Souji's equal in everything but cooking and normal social skills, quoting his butler Jiiya while expressing his intent to be the best at everything. But Tsurugi is unaware that he is actually the Scorpio Worm (スコルピオワーム, Sukorupio Wāmu), a Worm that killed the real Tsurugi and assumed his form while killing the man's older sister Mika. However, the Scorpio Worm's mind was completely overridden by the real Tsurugi's memories, believing himself to be Tsurugi while haunted by Mika's death to the point of disassociating himself as a Worm while vowing to kill them all. Jiiya kept Tsurugi in the dark of his true identity as the Kamishiro fortune had severely dwindled, Tsurugi becoming ZECT's hired exterminator as Kamen Rider Sasword (仮面ライダーサソード, Kamen Raidā Sasōdo). While Tsurugi is let go after Kagami becomes Gattack, he aids Souji after realizing Jiiya was teaching him to be a better person and the ways of noblesse oblige. Eventually learning of true nature as a Worm, a despairing Tsurugi aligns himself with the Worms to lead an all-out attack against the ZECT Riders. But this would turn out to be Tsurugi's plan to fulfill his promise by leading the Worms to slaughter, allowing Souji to fatally wound him with the Maximum Hyper Typhoon so Mika can be avenged before returning to his mansion to die in peace.

Tsurugi can transform into Sasword by using the Sasword Yaiver (サソードヤイバー, Sasōdo Yaibā) sword with the Sasword Zecter (サソードゼクター, Sasōdo Zekutā), which quells his Worm instincts. While his Masked Form is outfitted with Blood Vessel (ブラッドベセル, Buraddo Beseru) tubings that supply performance enhancing chemicals, Sasword can enter Rider Form to either access his Clock Up ability or perform his Rider Slash (ライダースラッシュ, Raidā Surashhu) finisher.

Tsurugi Kamishiro is portrayed by Yusuke Yamamoto (山本 裕典, Yamamoto Yūsuke).

Jiiya

A butler who serves the Kamishiro family, Jiiya (じいや) serves Tsurugi and often acts as a parental figure to him. He remains loyal to Kamishiro despite many of his rude actions. It seems that the Kamishiro wealth is no more, but Jiiya hides this fact from Tsurugi, finding ways to get money such as getting monetary reward for Sasword's killing of Worms, and after that transaction was cancelled, opening a ramen shop (which Tendou decides to take over as he sees Jiiya as too worthy to be doing this). He tells Kagami about Kamishiro's sister and her death at the hands of the Scorpio Worm. He has a younger twin brother who keeps the Legendary White Knife. He knows that Scorpio Worm is Tsurugi's true form but has chosen not to tell him because Tsurugi, as the last of the famous British Discabil family, must, in one form or another, carry on its name. Jiiya is respected by Tendou who refers to him as "Humanity's Treasure" due to his incredible skill as a chef. He has several students who hold him and high respect, and has published a cook book, which Tendou carries a copy of at all times. During the epilogue, it is revealed that he is the head cook for the Discabil Restaurant, which is owned by Misaki and named in his master's honor. 65 years old.

Jiiya is portrayed by Yasukiyo Umeno (梅野 泰靖, Umeno Yasukiyo).

Souji Tendou (Native)

The Native doppelganger of Souji Tendou is a man who uses the Dark Kabuto Zecter (ダークカブトゼクター, Dāku Kabuto Zekutā). This mimic version of Tendou was actually a human infant that was captured by Mishima and used for his experiments after being turned into a Native.

Hiro Mizushima, who already portrays Souji Tendou, also portrays his doppelganger counterpart.

ZECT

ZECT (ゼクト, Zekuto) is a mysterious organization that seemingly acts in order to destroy Worms, later revealed to have founded by the Native Worms who created both ZECT and the Masked Rider System to eliminate the Worms before conducting Negishi's own plans for humanity.

Worms

The Worms (ワーム, Wāmu) are Arthropod-like alien lifeforms that came from a meteor that devastated the city district of Shibuya seven years prior to the series' current timeline, the meteor being part of a larger one that greatly devastated Earth in the previous timeline depicted in the film Godspeed Love. The Worms are motivated to subvert and replace the population of an area they invade, possessing the ability to replicate the appearance and memories of another being whom they kill off. Worms believe that the original will live on as a part of them, since they adopt their victim's personality traits. But there are setbacks to this process as the Worms are unable to fully replicate aspects of their victims like their scent and can forced into their true forms through certain chemicals like makeup, few having his minds overridden by the memories of the identity they stole. The most basic of the Worms are Salis Worms (サリスワーム, Sarisu Wāmu), green chrysalis-like creatures with an albino variant called a Mutation Salis (ミューテーションサリス, Myūtēshon Sarisu). When threatened or endangered, a Salis Worm molts into a stronger form that can move at blinding speeds which comes from their high metabolism.

It would later be revealed that the current Worms are the second group to reach Earth, a previous group of Worms called the Natives came to Earth 35 years ago before the events of the series. Unlike their aggressive kin, the Natives learned to co-exist with humans with some creating their own human identities. They are also the ones who developed the Masked Rider System and ZECT for the purpose of fighting off the Worms.