Dopant

The Dopants (ドーパント, Dōpanto?) are the fictional antagonists in the Kamen Rider Series Kamen Rider Double. Dopants are normal humans who use Gaia Memories. The Gaia Memories are aspects of the true Gaia Memory (地球の記憶, Chikyū no Kioku?), the knowledge of everything on the Earth. These were originally accessed due to Philip's link to the Gaia Memory by means of the Gaia Library (地球（ほし）の本棚, Hoshi no Hondana?). But after he was taken from them, the Sonozaki Family uses a strange temple underneath their mansion to access the Gaia Memory. They then sell these to the highest bidder or to common criminals, all to reach their goal for the people of Futo to reach the next level of evolution. The name comes from the English words "dopant" and "doping". Dopants have the ability to disguise their voices, as female users have been able to make themselves sound like men.

Gaia Memories


A Gaia Memory (ガイアメモリ, Gaia Memori?) is a mysterious device resembling a USB flash drive that contains all of the Earth's knowledge of what it represents. This enables its user to become a Dopant, or in some special cases a Kamen Rider. Every Gaia Memory is adorned with the first letter of its name, stylized to reflect the powers it imbues on its user. For example, the Injury Memory (acquired by Shotaro and Philip before the series begins) resembles a broken bone in the shape of the letter I. In order to transform into a Dopant, the Gaia Memory is first inserted into a device called the L.C.O.G (Living Connector Setting Operation Gun), also called a Connect Shooter (コネクトシューター, Konekuto Shūtā?), which then produces a USB port-like tattoo on the user's skin called a Living Connector (生体コネクタ, Seitai Konekuta?). Whenever the Gaia Memory is pressed onto the Living Connector, it enters the user's body and transforms the user into a Dopant. This direct insertion will eventually drive its user insane from its addictive influence, which is why special belts called Memory Drivers (メモリドライバー, Memori Doraibā?) have been developed for use by high ranking members of the Museum to filter out these and other side effects. Kamen Riders utilize Gaia Memories that have been refined such that they can only be used in specialized Memory Driver belts. This refinement makes them resemble USB drives, rather than the ribcage design on Dopant Gaia Memories, and they may be weaker than Gaia Memories which are directly inserted.

To defeat a Dopant, a Kamen Rider has to use one of its Maximum Drive finishing attacks to eject and destroy the Gaia Memory, resulting in what is called a Memory Break (メモリブレイク, Memori Bureiku?). Evolved Gaia Memories require a direct strike on its location within the Dopant's body to execute the Memory Break. If the Dopant does not have a Living Connector, a Memory Break will not occur, however the Gaia Memory will still be ejected from the user's body. Dopants who use Memory Drivers are not susceptible to Memory Breaks.

Museum Dopants
Main Article: Sonozaki Family

Masquerade Dopants
Masquerade Dopants (マスカレイド・ドーパント, Masukareido Dōpanto) are Dopants used by the Sonozaki family as guards and other forms of agents. Mass produced Masquerade Memories (マスカレイドメモリ, Masukareido Memori) are distributed to their Gaia Memory salesmen for the purpose of producing more thugs to do their dirty work. The Masquerade Dopants differ from other Dopants as they retain human form, wearing suits with masks that have a spine and rib cage design, resembling the bony design of the Dopant GaiaMemories and to an extension the Shocker Soldiers and all of their varients. Also unlike major Dopants, they are much weaker and don't require a Maximum Drive to defeat neither do they return to human form when defeated as they are literally destroyed.

Weather Dopant
Shinkuro Isaka (井坂 深紅郎, Isaka Shinkurō?) is the mysterious man with the W Memory (Ｗ（ダブリュー）のメモリを持つ男, Daburyū no Memori o motsu otoko?), who gained the Weather Memory in the past and tested its abilities via a string of murders that, among several electrocution, drowning, and freezing deaths, included the murder of Ryu Terui's parents and younger sister. He also serves as the head physician at the Isaka Medical Clinic (井坂内科医院, Isaka Naika Iin?), however his specialty is in Dopant physiology, benefitting from the Sonozaki Family's influence in Futo. Having encountered Ryubee in the past and witnessed the power of the Terror Memory, Isaka made it his mission to get the Terror Memory for himself. He began experimenting with several Gaia Memories, leaving his body riddled with Living Connectors, until he settled on the W Memory. This direct insertion of Gaia Memories has not affected his personality, as it was already sadistic before he began using them. When his identity is discovered, he takes refuge in the Sonozaki estate where he convinces Saeko to take down her father for both of their goals to be met. As the Weather Dopant (ウェザー・ドーパント, Wezā Dōpanto?), he is armed with a whip called the Weather Mine (ウェザーマイン, Wezā Main?) and he has control all aspects of the weather: intense sunlight, heavy rain, lightning, tornadoes, and freezing snow. Isaka also claims that he has absorbed the powers of other Gaia Memories in the past, as he planned to do with the Invisible Memory and does with the Quetzalcoatlus Memory. The Weather Dopant is also physically stronger than most other Dopants, as he is able to withstand Maximum Drives, Twin Maximums, and the Xtreme Memory's Maximum Drive. However, the Weather Dopant is finally defeated by Kamen Rider Accel Trial's Machine Gun Spike Maximum Drive, which destroys the Weather Memory. With it and the Quetzalcoatlus Memory destroyed, Isaka's body becomes covered with Living Connectors which causes him to dissolve away.
 * Statistics
 * Identity: Shinkuro Isaka
 * Gaia Memory: Weather Memory
 * Memory Break: Machine Gun Spike
 * Actor: Tomoyuki Dan
 * Episodes: 20-36

Magma Dopant
After being fired from his position at Windscale, Yousuke acquires the Magma Memory, imbuing him with pyrokinetic abilities. However, while exacting his revenge against Windscale, Yousuke is consumed by the Gaia Memory's power and goes on a rampage. Shotaro finds Yousuke at the fifth Windscale building and defeats him as Double. Before Yousuke can be handed over to the police, he is abducted and murdered by the T-Rex Dopant.
 * Statistics
 * Identity: Yousuke Togawa
 * Gaia Memory: Magma Memory
 * Actor: YOH
 * Episodes: 1
 * Memory Break: Kamen Rider Double CycloneJoker's Joker Extreme

T-Rex Dopant
The T-Rex Dopant can cause massive shockwaves with its roars and can use debris to form a robotic T. rex body called the Big T-Rex to increase its powers. After being fired from her position as Windscale's top designer, Marina Tsumura buys the T-Rex Memory with her boyfriend Yousuke to exact their revenge for both being fired. However, when Yousuke goes berserk, Marina hires her childhood friend Shotaro to find Yousuke so she can kill him. After Shotaro learns the truth and Marina tries to kill him, he defeats her as Double, destroying the T-Rex Memory, and hands her over to the authorities.
 * Statistics
 * Identity: Marina Tsumura
 * Gaia Memory: T-Rex Memory
 * Actor: Meibi Yamanouchi
 * Episodes: 1-2
 * Memory Break: Kamen Rider Double HeatMetal's Metal Branding

Marina Tsumura is portrayed by Meibi Yamanouchi (山内 明日, Yamanouchi Meibi?).[2] She previously portrayed Rin in Mahou Sentai Magiranger.

Money Dopant
Kaga is a life-long gambler who is able to use others' tells to win. He is also the owner of the secret Million Colosseo casino, tricking debtors into having them bet their life force in a game of chance, using his Dopant power to seal it into pseudo-memories called, Life Coins after they lose. As he holds the Life Coins in his Dopant body, his destruction would cause all of the people to die. Shotaro and Philip are able to beat Kaga out of Life Coins in a winner takes all game of old maid. After the Money Dopant is defeated and the Money Memory broken, the Life Coins are unsealed and everyone is returned to normal.
 * Statistics
 * Identity: Taizo Kaga
 * Gaia Memory: Money Memory
 * Actor: Tatsuya Gashuin
 * Episodes: 3-4
 * Memory Break: Kamen Rider Double HeatMetal's Metal Branding

Anomalocaris Dopant
The childish Genzo Takamura works as the head of one of the many Gaia Memory manufacturing centers scattered throughout Futo. As the Anomalocaris Dopant, he can travel underwater, fire his fangs as if they are bullets, and transform into a giant form called the Big Anomalocaris. Due to the fact that councilwoman Miyabi Kusuhara is continuing her late husband's plans to build the Second Futo Tower and Ryubee Sonozaki sees it as a threat to his enterprise, Takamura is given the order to assassinate her. After giving a proto-model of his Anomalocaris Memory, a production-model, to his friend so he can serve as a decoy, Genzo later kidnaps the councilwoman's daughter Asuka to lure her mother into a trap. However, the Anomalocaris Dopant is defeated by Kamen Rider Double.
 * Statistics
 * Identity: Genzo Takamura
 * Gaia Memory: Anomalocaris Memory
 * Actor: Takaaki Ito
 * Episodes: 5-6
 * Memory Break: Kamen Rider Double CycloneJoker's Joker Extreme (Prototype), Double LunaTrigger's Trigger Full Burst

Cockroach Dopant
Ikari is a sociopathic dōjinshi artist who runs the Dark Bug Exterminator website, a blog where people write down the names of those they want dead and he carries out the deed as the Cockroach Dopant, writing about his adventures in his self-published manga as the hero "Gokistar". His Dopant abilities include the ability to climb along walls and to move faster than oncoming attacks, much like a cockroach. Only Kamen Rider Double LunaTrigger's homing attacks are able to hit him, but with his speed he steals the Luna, Trigger, Heat, and Metal Memories from Double. Ikari then decided to take the rest of Double's arsenal to become more powerful. However, after Philip learns the Heaven's Tornado dance and uses it against the Cockroach Dopant, the Gaia Memories are retrieved and a defeated Ikari is left for the police.
 * Statistics
 * Identity: Ikari
 * Gaia Memory: Cockroach Memory
 * Actor: Jin Katagiri
 * Episodes: 7-8
 * Memory Break: Kamen Rider Double LunaTrigger's Trigger Full Burst

Sweets Dopant
Yukiko Sasaki is a maid at the Sonozaki estate with a sweet tooth that she cannot satisfy, only able to be a food critic instead of a pâtissière because she could not cook very well. In her Dopant form, she is able to fire a whip cream that hardens like cement to trap her enemies. As the Sweets Dopant, Yukiko kidnaps the the top pâtissiers hired by the Sonozaki family by dragging them in her "Sweets Cream" state to a small building on the grounds to make pastries only for her. However, when Akiko attempts to weed out the wrong culprit with her sweets, Yukiko kidnaps her with Mai Asakawa, the daughter of her previous victim. Though intending to kill Akiko for disgracing her love for sweets, the Sweets Dopant is battered by Akiko using a chair before Kamen Rider Double finishes her off.
 * Statistics
 * Identity: Yukiko Sasaki
 * Gaia Memory: Sweets Memory
 * Actor: Maha Hamada
 * Episodes: 9-10
 * Memory Break: Kamen Rider Double HeatJoker's Joker Grenade

Virus Dopant
The Virus Memory normally enables the user to unleash a plague that can wipe out an entire city, yet is weak against fire-based attacks. The Memory came into the possession of Sachi Yamamura, shortly after she saw that her fiance was a con man who uses women. While on her way home, having second thoughts about using it to exact her revenge, she is run down by a car driven by a group of thugs. Before she is hit, she uses the Gaia Memory but becomes comatose before the transformation completes. However, her consciousness enters a wrecked SUV which is rebuilt and she uses her brother's emotions to make him drive the SUV to take revenge on the thugs until Kamen Rider Double destroys the SUV. She then uses the Virus Dopant's physical form to chase after her fiance, becoming consumed by the Gaia Memory, until it is destroyed by Kamen Rider Double.
 * Statistics
 * Identity: Sachi Yamamura
 * Gaia Memory: Virus Memory
 * Actor: Rinako Matsuoka
 * Episodes: 11-12
 * Memory Break: Kamen Rider Double HeatTrigger's Trigger Explosion

Violence Dopant
Tsuyoshi Ageo is Wakana's manager, a spineless man who loves her in spite of the abuse. Ageo is used by Wind Wave DJ Motoko Saeki in a scheme to force Wakana off the air, giving him the Violence Memory she bought. Overcome by the Memory's influence, Ageo assumes the alias of "Mister Question", targeting certain places of value to Wakana and portraying himself as a stalker. As the brutish Violence Dopant, his left arm is strong enough to destroy anything in its path, even enough to smash through cars. He can compress his body into a wrecking ball-like form called the Violence Ball to cause more collateral damage. Once found out, the Violence Dopant points Wakana to Motoko before Double defeats him.
 * Statistics
 * Identity: Tsuyoshi Ageo
 * Gaia Memory: Violence Memory
 * Actor: Hiromichi Miyoshi
 * Episodes: 13-14
 * Memory Break: Kamen Rider Double LunaTrigger's Trigger Stag Burst

Arms Dopant
Kenji Kurata, part of the Twin Rose (ツインローズ�Tsuin Rōzu? ) burglar team with partner Fuyumi Aso (麻生 冬実 Asō Fuyumi? ), is hired by Saeko to lure Philip out of hiding. Given the Arms Memory, it turns Kurata into a uncontrollable sadist as he turns his back on Fuyumi and the morals they followed. Able to morph his left forearm into a variety weapons such as a sword, the Arms Dopant goes on a burglary spree and claims to be a Kamen Rider to force Double into the trap, only able to capture Shotaro and Akiko to use as hostages. However, the unexpected return of Kamen Rider Double FangJoker, and eventual control of the form, turns the tables as the defeated Kurata is left for the police.
 * Statistics
 * Identity: Kenji Kurata (倉田 剣児 Kurata Kenji? )
 * Gaia Memory: Arms Memory (アームズメモリ Āmuzu Memori? )
 * Actor: Kōichirō Nishi (西 興一朗 Nishi Kōichirō? )
 * Episodes: 15-16
 * Memory Break: Kamen Rider Double FangJoker's Fang Strider

Kenji Kurata is portrayed by Kōichirō Nishi (西 興一朗, Nishi Kōichirō?).[9] He previously portrayed Ryouga Hakua in Bakuryū Sentai Abaranger.

Bird Dopant
Akane is a middle school girl selected by Saeko to test the limits of one of the newest Gaia Memories: the Bird Memory. In addition to the fact that no one under the age of 20 is allowed to use a Gaia Memory, the Bird Memory can also be used by those without a Living Connector and it has an addictive side effect. When Akane runs away from home, her friend Touma is the first to test the true powers of the Bird Memory out and decides to use it for fun with Yuichi and Yayoi until Touma decides to use it to attack people. They are stopped by Kamen Rider Double, and the two boys are taken into the hospital after suffering from some of the negative side effects of using a Gaia Memory without a Living Connector. Later, Akane is overpowered by withdrawal from the Bird Memory and attacks Philip who gets in her way of obtaining it. Consumed completely by the Gaia Memory, Akane is able to access the Bird Dopant's Strengthen Form (強化態 Kyōkatai? ), only to be defeated after the Nasca Dopant assists Kamen Rider Double in finding the Bird Dopant's weak spot for a direct strike on the Bird Memory.[10]
 * Statistics
 * Identities: Akane Egusa (江草 茜 Egusa Akane?, 18), Touma Fujikawa (藤川 統馬 Fujikawa Tōma? , 17), Yuichi Kanamura (金村有一 Kanamura Yūichi? , 17), Yayoi Kubota (久保田 弥生 Kubota Yayoi? )
 * Gaia Memory: Bird Memory (バードメモリ Bādo Memori? )
 * Actor: Mana Konno (今野 真菜 Konno Mana? ), Haruki Kimura (木村遼希 Kimura Haruki? ), Takuya Yoshihara (吉原 拓弥 Yoshihara Takuya<sup style="line-height: 1em; ">? ), Manami Ikura (伊倉 愛美 Ikura Manami<sup style="line-height: 1em; ">? )
 * Episodes: 17-18
 * Memory Break: Kamen Rider Double FangJoker's Fang Strider (Touma), Double CycloneTrigger's Trigger Bat Shooting (Akane)

IceAge Dopant
Originally only known as the icy Dopant (氷のドーパント, Kōri no Dōpanto?), the IceAge Dopant has the ability to make absolute zero ice from attacks to clones. Kiyoshi was the son of flower coordinator Makiko Katahira (片平 真紀子, Katahira Makiko?), who received bad press due to her son's actions. Obtaining the IceAge Memory, Kiyoshi uses it to attack anyone who makes him mad such as Shotaro when he unintentionally shoved Kiyoshi out of the way while looking for Makiko. After his clone was destroyed by Accel, believing the Dopant to be the one he is looking for, Kiyoshi runs into his mother as she takes the Gaia Memory from him to take the blame for the attack. However, Shotaro uncovers the truth as IceAge Dopant is defeated and Ryu Terui arrests Kiyoshi instead of killing him in revenge, only to learn that Kiyoshi is not his target.
 * Statistics
 * Identity: Kiyoshi Katahira (片平 清 Katahira Kiyoshi<sup style="line-height: 1em; ">? )
 * Gaia Memory: IceAge Memory (アイスエイジメモリ Aisueiji Memori<sup style="line-height: 1em; ">? )
 * Actor: Kento Shibuya (渋谷 謙人�Shibuya Kento<sup style="line-height: 1em; ">? )
 * Episodes: 19-20
 * Memory Break: Dynamic Ace

Kiyoshi Katahira is portrayed by Kento Shibuya (渋谷 謙人, Shibuya Kento?).<sup class="reference" id="cite_ref-10">[11] He previously played Tsutomu Tsumura in Kamen Rider Hibiki.

Triceratops Dopant
Aya Kujo is a former FPD officer who transfered to the LAPD under encouragement from her partner Masaki Mizoguchi, whom she loved. After the scrunity and disappearance of Mizoguchi, Aya returns to Futo and purchases the Triceratops Memory in order to take revenge against the men responsible for Mizoguchi's disappearance and death: the crooked cops Himuro and Ken Akutsu. As the Triceratops Dopant, she possesses superhuman strength, can generates spheres of plasma, and uses the Dinosaur Club (ダイノソアクラブ, Dainosoa Kurabu?) as her weapon. However, after killing off Himuro and Akutsu, Aya's revenge shifts to Futo as the Gaia Memory's corruptive powers begin to take hold. She eventually gains the ability to transform into a giant bipedal Triceratops called the Big Triceratops (ビッグ・トライセラトップス, Biggu Toraiseratoppusu?) before Kamen Rider Accel stops her with his new Gunner A support robot.
 * Statistics
 * Identity: Aya Kujo (九条 綾, Kujō Aya?)
 * Gaia Memory: Triceratops Memory (トライセラトップスメモリ, Toraiseratoppusu Memori?)
 * Actor: Ayumi Kinoshita (木下 あゆ美, Kinoshita Ayumi?)
 * Episodes: 21-22
 * Memory Break: Kamen Rider Accel's AccelGunner Gaia Cannon

Aya Kujo is portrayed by Ayumi Kinoshita (木下 あゆ美, Kinoshita Ayumi?).<sup class="reference" id="cite_ref-11">[12] She previously portrayed Marika "Jasmine" Reimon in Tokusou Sentai Dekaranger.

Liar Dopant

 * Statistics
 * Identity: Sachio Sawada
 * Gaia Memory: Liar Memory (ライアーメモリ, Raiā Memori?)
 * Actor: Moro Morooka (モロ 師岡)
 * Memory Break: Joker Extreme

Sachio Sawada (沢田 さちお, Sawada Sachio) is a street calligrapher and poet who uses the Liar Memory to become the Liar Dopant (ライアー・ドーパント, Raiā Dōpanto), referred to in urban legends as the Radio Tower Clown (電波塔の道化師, Denpatō no Dōkeshi). Armed with the Lie Speaks (ライスピークス, Rai Supīkusu), a staff with a large speaker in a shape of a giant mouth that can shoot energy projectiles, the Liar Dopant's signature move is converting any lie he says into his Lie Needles (ライニードル, Rai Nīdoru), forcing whoever it hits to fall under the Dopant's deception. Though he is paid by Yukiho to help Jimmy win the Fuuuuuutic Idol (フーティックアイドル, Fūtikku Aidoru) competition, he turns on her after she fails to pay him his ideal amount, revealing the ruse in front of Jimmy. Once his cover is blown, and his being a fan of Wakana's radio show used against him, the Liar Dopant is defeated through the combined powers of Kamen Riders Double & Accel, with Double dealing the Memory Break using CycloneJoker's Joker Extreme.
 * Episodes: 23-24

Puppeteer
Keio Horinouchi (堀之内 慶應, Horinouchi Keiō?) is a children's author who has gained commercial success for his book The Girl and the Dollhouse (少女と人形の家, Shōjo to Ningyō no Ie?) which he wrote to reflect his feelings for his daughter Rikako who died several months ago. As the Puppeteer Dopant (パペティアー・ドーパント, Papetiā Dōpanto?), he uses special puppet strings to take control of whatever he wishes and carries a flute that produces super-sonic waves. He uses these powers to take revenge against those who give his book harsh criticism by controlling his daughter's doll, Riko, as the instrument of his vengence. After being exposed, getting a new puppet in Wakana by Isaka, Horinouchi turns his attention towards Akiko before being defeated by Kamen Rider Double CycloneMetal's Metal Twister Maximum Drive.
 * Statistics
 * Identity: Keio Horinouchi
 * Gaia Memory: Puppeteer Memory
 * Actor: Wataru Shihoudou (四方堂 亘, Shihōdō Wataru?).
 * Memory Break: Metal Twister
 * Episodes: 25-26

Invisible
Lily Shirogane (リリィ白銀, Riryi Shirogane?) is a popular magician trying to follow in her grandfather Frank's footsteps. To emulate his most popular trick, the disappearing lady, Lily is given the Invisible Memory by Dr. Isaka, turning her into the Invisible Dopant (インビジブル・ドーパント, Inbijiburu Dōpanto?). Unbeknownst to her, Isaka modified the Invisible Memory such that she does not turn into a monstrous Dopant and making it impossible to remove from her body. She initially goes to the Narumi Agency for help in finding the man who gave it to her under the pretense that she wishes to have it removed, but instead she wants to be able to control the invisibility. Isaka agrees, stabilizing the GaiaMemory, only because he knows it will eventually kill her and he will be able to take it from her after she dies, giving him the power of invisibility without the Dopant transformation. However, by killing her and using his EngineBlade as a defribilator to quickly revive her, Kamen Rider Accel removes the Invisible Memory and crushes it.
 * Statistics
 * Identity: Lily Shirogane
 * Gaia Memory: Invisible Memory
 * Actor: Nao Nagasawa (長澤 奈央, Nagasawa Nao?)
 * Memory Break: EngineBlade attack
 * Episodes: 27-28

Lily is portrayed by Nao Nagasawa (長澤 奈央, Nagasawa Nao?). She previously portrayed Nanami Nono on Ninpuu Sentai Hurricanger.

Nightmare
Hajime Fukushima (福島 元, Fukushima Hajime?) is a Futo University student who also works as an assistant to Professor Akagi. He is in love with another university student named Himeka Yukimura when she called him her "prince" but learns that she calls evert male that assists her, at the thought of never being loved back he suffered from insomnia. He purchased the Gaia Memory to give Himeka the same amount of pain by never giving her a good night sleep. As the Nightmare Dopant (ナイトメア・ドーパント, Nightmare Dōpanto?) Fukushima has the ability to enter peoples' dreams as well as manipulate them in his favor. He traps his victims in their dreams and uses a massive dreamcatcher-like net to place them in a coma. The victims are branded with a letter H on their forehead, for Hajime and Himeka. He does this to trap his rivals in their worst nightmare. Outside of dreams the Dopant's only known ability is to shoot energy projectiles. However in dreams the Dopant's powers are unaffected by a person's pure conciousness, as demonstrated by Phillip. While Fukushima faked being a victim himself he is found out by Shotaro and defeated by LunaMetal
 * Statistics
 * Identity: Hajime Fukushima
 * Gaia Memory: Nightmare Memory
 * Episodes: 29-30
 * Memory Break: Metal Illusion

Beast

 * Statistics
 * Identity: Maruo Arima
 * Gaia Memory: Beast Memory
 * Episodes: 31-32
 * Memory Break: Bicker Charge Break

Maruo Arima (有馬 丸男, Arima Maruo?) is a bank robber who uses his destructive and self-regenerative powers as the Beast Dopant (ビースト・ドーパント, Bīsuto Dōpanto?) to attack armored cars. He was given the Beast Memory ten years ago, and was being investigated by Sokichi Narumi until the evidence went dry. The return of Narumi's partner Isamu Bitō to the detective agency leads Shotaro and Philip to investigate the crimes in the present day. He is weakened by CycloneJokerXtreme's Prism Break Maximum Drive before being eventually defeated by the Bicker Charge Break.

Maruo Arima is portrayed by Katsuya (勝矢?).

Zone
Suzuko Arima (有馬 鈴子, Arima Suzuko?), the wife of Maruo Arima, uses the powers of the Zone Dopant (ゾーン・ドーパント, Zōn Dōpanto?) to teleport anything it sees into a different area, similar to moving the pieces of a shogi board. In the past, Suzuko used these powers to assist her husband in his crime wave. However, she lost the Gaia Memory ten years ago and it was found by Sokichi Narumi, and he then hid it in a bear statue he kept in a vacation cabin. When Shotaro finds it and discovers that it is Suzuko's, she distracts him and takes it from him, enabling her to attack him and help Maruo once more. She is defeated by the Bicker Finallusion Maximum Drive.
 * Statistics
 * Identity: Suzuko Arima
 * Gaia Memory: Zone Memory
 * Episode: 32
 * Memory Break: Bicker Finallusion

Suzuko Arima is portrayed by Ryoko Gi (魏 涼子, Gi Ryōko?).

Yesterday
Yukie Sudo (須藤雪絵, Sudō Yukie?) is the younger sister of Kirihiko Sonozaki, and has come to Futo to take revenge against Saeko Sonozaki for her brother's death. With the powers of the Yesterday Dopant (イエスタデイ・ドーパント, Iesutadei Dōpanto?), she is able to force anyone to relive the actions of the previous day. Unlike most Dopants, she retains all of her intellect and is not driven insane by the Memory, making her able to execute extremely complex manipulations through skillful use of Yesterday. After attacking landsharks who threatened to take down her old elementary school, she sets up Shotaro as a makeshift assassin to kill off Saeko by going under the alias Yuko Fuwa and asking Shotaro to supposedly help find a missing cat named Kinou (literally meaning 'yesterday') until Accel gets in the way and her control over Double is eliminated. Her real plans however were to get close to the Museum to get a better chace of exacting revenge by putting Saeko in a 'yesterday trance.' But this plan backfires after the altering done by Isaka to Saeko's Taboo Dopant form to have Yukie be put into the trance instead. When Double uses Prism Break the trance is broken and when she regains conscious after the Memory Break she remembers about the time she shared with her brother while also gaining amnesia as a side effect of the Yesterday Memory.
 * Statistics
 * Identity: Yukie Sudo
 * Episodes: 33-34
 * Memory Break: Prism Break

Yukie Sudo is portrayed by Kaoru Hirata (平田 薫, Hirata Kaoru?).<sup class="reference" id="cite_ref-18">[19] She previously portrayed Yuka Yamazaki in Mahou Sentai Magiranger.

Quetzalcoatlus
Nagisa Shimamoto (島本 凪, Shimamoto Nagisa?) is a worker at the Futo Aviary who becomes the unwilling subject of Isaka's experimentation with the powers of the Quetzalcoatlus Dopant (ケツァルコアトルス・ドーパント, Ketsarukoatorusu Dōpanto?). The fear she has of Isaka causes the Living Connector to mutate, making the Quetzalcoatlus Memory stronger (the Gaia Memory appears to have its own set of wings) for Isaka to use for his own purposes. Isaka makes a copy of the Quetzalcoatlus Memory and uses it on a Red-and-green Macaw to threaten Shotaro with a sample of the Memory's powers as the giant Quetzalcoatlus Dopant drags Nagi off until Kamen Rider Double saves her. This incarnation of the Dopant is defeated by CycloneJoker Xtreme's Bicker Charge Break Maximum Drive, but the Quetzalcoatlus Memory still exists for Isaka to use on himself later. After the Weather Dopant is defeated by Kamen Rider Accel Trial, the Quetzalcoatlus Memory is ejected from Isaka's body and it is destroyed by Accel Trial.
 * Statistics
 * Identity: Nagisa Shimamoto; Unnamed Macaw (Copy); Shinkuro Isaka (absorbed power)
 * Episode: 35
 * Memory Break: Bicker Charge Break (Copy); crushed by Accel Trial (Real)

Nagisa Shimamoto is portrayed by Miyuu Wagawa (和川 未優, Wagawa Miyū?).

Movie Dopants
In Kamen Rider × Kamen Rider Double & Decade: Movie War 2010's Kamen Rider Double: Begins Night, Masquerade Dopants appear in the movie as well.

Death Dopant
The Death Dopant (デス・ドーパント, Desu Dōpanto?), has the ability to bring anyone back from the dead and carries a scythe with a white dummy attached to it. It was defeated by Kamen Rider Skull at an unknown time. It's appearance was used by the Dummy Dopant in a plot he devised.
 * Statistics
 * Gaia Memory: Death Memory
 * Memory Break: Unnamed Kamen Rider Skull Maximum Drive

Dummy Dopant

 * Statistics
 * Gaia Memory: Dummy Memory
 * Identity: Father Robert Shijima
 * Actor: Toru Tezuka (手塚 とおる, Tezuka Tōru?)

Father Robert Shijima (神父・ロベルト志島, Shinpu Roberuto Shijima?) is a figure within the cult known as the Order of Silence and Darkness. Shijima can become the Dummy Dopant (ダミー・ドーパント, Damī Dōpanto?) who can assume any form he wishes. Among these forms are Sokichi Narumi and the Death Dopant. Using the Death Dopant's form, Shijima plays with the heads of high class people by assuming the forms of those recently deceased to con them into an early grave and assume their identities. One such con involve him assuming the form of Erika Mutsuki, Asami's sister. But once exposed, the Dummy Dopant evades Double as he finds himself in the the middle of Decade's fight with Super Shocker, where he takes control of the Mammoth Mecha (マンモスメカ, Manmosu Meka?). However, the Dummy Dopant meets his end when he is assimilated by the Neo Organism as it becomes the inhuman Ultimate D. In materials to promote the film, the Dummy Dopant was referred to as the "mysterious Dopant" (なぞのドーパント, nazo no Dōpanto?).