This article is about a/an Villain in Kamen Rider W.

Maruo Arima (有馬 丸男 Arima Maruo), also known as Maru (マル), is Beast Gaia Memory user and Suzuko Arima's husband.

Character History

Kamen Rider W

He is a bank robber who a decade ago, attempted an armored car robbery at the Futo Dam with his wife Suzuko. The case was investigated by Soukichi Narumi until the evidence went dry and when Isamu Bito turned himself in for the crime. By the present, now rich, Maruo is still looking for a bear statue that holds the Zone Memory. However, he meets resistance from Kamen Riders Double and Accel, but he defeats them easily. Once the Zone Memory returns to Suzuko's possession, the two return to the Futo Dam to finish their heist, after quickly besting the Riders. There, they face Accel once again, but just when it seems Maruo and Suzuko are going to win, Double arrives. Double pushes himself to his limit fighting Maruo, and beyond, achieving Double's perfect synchronization form; CycloneJoker Xtreme. The Beast Dopant is weakened by Kamen Rider Double CycloneJoker Xtreme's Prism Break Maximum Drive before being eventually defeated by the Bicker Charge Break Maximum Drive.

OOO, Den-O, All Riders: Let's Go Kamen Riders

Beast Dopant is seen as a member of Shocker due to the events of the altered timeline. After the Double Riders betray Shocker, he is seen with other monsters approaching them, but he is kicked away by Kamen Rider V3.

Super Hero Taisen Z

to be added

Dopant Form

Beast Dopant

Beast Dopant

Main article: Beast Dopant
―Transformation announcement[src]
  • Height: 235cm
  • Weight: 210kg

By gained the Beast Memory, he can transform into the Beast Dopant (ビースト・ドーパント Bīsuto Dōpanto) with superhuman strength and self-regenerative powers.


  • Maruo's Beast Dopant form is likely a reference to the protagonist of Beauty and The Beast, Adam, who once turned into a monster namely "Beast".

External Links

Narumi Detective Agency
Shotaro Hidari - Philip - Akiko Narumi - Sokichi Narumi† - Tokime
Double Driver - Accel Driver - Lost Driver - Gaia Memories - Memory Gadgets - Fang Memory - Xtreme Memory - Trial Memory - Gaia Memory Enhancing Adapter - Metal Shaft - Trigger Magnum - Engine Blade - Skull Magnum - Prism Bicker - Eternal Edge - RevolGarry - HardBoilder - Gunner A - Shroud Magnum - SkullBoilder - SkullGarry
The Fuuto Irregulars
Santa-chan - Watcherman- Queen & Elizabeth - Isamu Bito
Futo Police Department
Ryu Terui - Mikio Jinno - Shun Makura
Museum and the Dopants
Foundation X
The Sonozaki Family: Terror - Claydoll - Taboo/R Nasca - Nasca - Smilodon - Masquerade Dopants
Dopants: Magma Dopant - T-Rex Dopant - Money Dopant - Anomalocaris Dopant - Cockroach Dopant - Sweets Dopant - Virus Dopant - Violence Dopant - Arms Dopant - Bird Dopant - Ice Age Dopant - Triceratops Dopant - Liar Dopant - Puppeteer Dopant - Invisible Dopant - Nightmare Dopant - Beast Dopant - Zone Dopant - Yesterday Dopant - Quetzalcoatlus Dopant - Gene Dopant - Jewel Dopant - Old Dopant - Utopia Dopant - Energy Dopant
Movie Exclusive Villains: Dummy Dopant - Heat Dopant - Trigger Dopant - Metal Dopant - Luna Dopant - Cyclone Dopant - Bat Dopant - Spider Dopant - Kamen Rider Eternal - Commander Dopant - Eyes Dopant
Manga Exclusive Villains (Futo Detective): Road Dopant - Aurora Dopant - Meganeura Dopant -Brachiosaurus Dopant - Scream Dopant - Alcohol Dopant - Puzzle Dopant - Reactor Dopant - Antlion Dopant - Owl Dopant - Trash Dopant
Katsumi Daido - Maria S. Cranberry - Reika Hanehara - Kyosui Izumi - Gozo Domoto - Ken Ashihara
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