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.
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.
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.
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.
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.
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.
While Tsurugi is let go after Arata becomes Gattack, he aids Souji after realizing Jiiya was teaching him to be a better person and the ways of noblesse oblige.
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.
He has several students who hold him and high respect, and has published a cook book, which Souji carries a copy of at all times.
At first she is a "by-the-book" tough as nails character; however, she soon begins to question the actions of ZECT and eventually gains respect for Souji after he rescues her from the Worms.
As the series progressed, Yuzuki slowly began to reciprocate to Tsurugi's feelings, and accepted his request to spend Christmas Day with him.
Unfortunately, Tsurugi became aware of the fact he was Scorpio Worm and was eventually destroyed in battle by Kabuto, despite Misaki's pleas to stop.
Sou Yaguruma (矢車 想, Yaguruma Sō) is originally a ZECT agent who was the original user of the TheBee Zecter (ザビーゼクター, Zabī Zekutā) and the first, having command of his personal army of ZECT Troopers called Shadow (シャドー, Shadō) during his time as Kamen Rider TheBee (仮面ライダーザビー, Kamen Raidā Zabī).
A perfectionist believing in a philosophy known as "Perfect Harmony" (完全調和, Kanzen Chōwa), his composure and strict teamwork ethic conceal his arrogance and temper which Souji exploited to reveal a security flaw within his group.
Sou's obsession to take out Souji resulted with the TheBee Zecter abandoning him with his former subordinate Shun Kageyama firing him instead of keeping him in Shadow as an advisor.
After all of the enemy Worms are wiped out, Yaguruma puts a mutating Shun out of his misery while seeking to honor his promise for them to see the northern lights.
As KickHopper, he uses the Anchor Jack (アンカージャッキ, Ankā Jakki) joints on his left leg to either jump around or perform a Rider Kick.
He is defeated by Hyper Kabuto's and Gatack's Rider Kick and then destroyed by the meteorite explosion that obliterated the studio set.
Prior to meeting Souji, she had eaten nothing but dry boiled rice for the last seven years of her life, considering the concept of taste and deliciousness a sin.
After accepting Souji as her superior, she began to work at the Bistro la Salle, although she often misinterpreted recipes and created horrible dishes as a result.
One of the leaders of the Natives, Negishi (根岸) seems like a fun loving person despite the deep respect ZECT offers to him.
In addition, they also carry a grenade launcher-like shotgun as a last resort and means of retreating, also they use flash bombs which disable Worms and seem to prevent them from molting.
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.
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.
When threatened or endangered, a Salis Worm molts into a stronger form that can move at blinding speeds which comes from their high metabolism.
His first form, Cassis Worm Dimidius (カッシスワーム・ディミディウス, Kasshisu Wāmu Dimidiusu), has the capability of "Freeze", which is activated by clenching his left fist.
After his demise, he evolved into a stronger form Cassis Worm Gladius (カッシスワーム・グラディウス, Kasshisu Wāmu Guradiusu) by use of the ability, "Life of Immortality".
After his demise, he evolved split into two entities and assumes a new form of Cassis Worm Clipeus (カッシスワーム・クリペウス, Kasshisu Wāmu Kuripeusu).