Demushu

Demushu (voiced by Tomokazu Sugita) is one of the last survivors of the Femushinmu civilization, having been transformed into a red Over Lord Inves before slaughtering countless weaker members of his kind when his world was touched by the Helheim Forest.

When the cracks opened the way to Helheim's next target, Earth, Demushu seek to crush the weak of the human civilization, gaining a rival in Kaito Kumon (Armored Rider Baron). However, he ultimately fell to the power of Gaim's Kiwami Arms.

When the cracks opened the way to Helheim's next target, Earth, Demushu seek to crush the weak of the human civilization, gaining a rival in Kaito Kumon (Armored Rider Baron). However, he ultimately fell to the power of Gaim's Kiwami Arms.

When Kaito was searching for Demushu, the Over Lord Inves summons several Elementary Inves to attack Baron so he can escape.

It later picks up a pioneer plaque and a Japanese Dictionary that Kaito left to lure it out. Demushu soon meets Kaito in the ruin and talks in a strange language. He also only responds by tossing the plaque and ripping the dictionary, leaving Kaito no choice but to fight. However, Demushu proves to be very strong, even controlling the Helheim's plants easily and pinning Baron to the ground.

Before the Over Lord could finish off Baron, Marika appears to distract Demushu as they retreat. Later, Sagara, as a hologram approached the Over Lords as he somehow knew what are they saying. As Gaim searches for the Over Lords in the ruins, Demushu fought him without mercy while Redyue was still reading the dictionary. Before Demushu could finish off Kouta, Redyue stops him and binds Kouta with the Helheim plants as they leave, dropping the Rider as a result of their absence.

Demushu was found by Kaito again, however Baron managed to fight back in Lemon Energy Arms as the Over Lord was overpowered. While fighting, the Over Lord could finally speak Japanese much to Baron's surprise. Before they could finish each other, Gaim appears to stop them before Redyue convinces Demushu to retreat.

Later, Demushu attacked the researchers as he was searching for Kaito. However while fighting Zangetsu Shin and Gaim, Rosyuo ordered the Over Lord telepathically to retreat as Demushu couldn't handle the sound wave from Rosyuo.

He was later punished by his master for attacking the humans.

Demushu arrive where Gaim and Zangetsu Shin were as he started to attack them. Sigurd appears to fight the Over Lord and demanded him about the Forbidden Fruit. While fighting, a Crack started to open as he enters it which lead him to Zawame.

Arriving in Zawame City, Demushu starts to destroy the city, seeing that the city is very ugly. He later fight both Gaim and Baron, but he managed to defeat them. He also explains to Kouta that he lives for battle and those who were weak won't survive. An enraged Kouta becomes Gaim Kachidoki Arms and battles with Demushu. Demushu would have been defeated, if only Marika and the Kurokage Troopers didn't interfere with Gaim. With Gaim overpowered, Demushu takes the chance to defeat him. After Kaito escapes with an injured Kouta, Demushu battles Marika and the Kurokage Troopers, with Baron Lemon Energy Arms and Knuckle soon join the fray.

After he gets injured from Kurokage Troopers, Baron, Knuckle and Marika's attacks, Demushu flees to the safe place where the Helheim fruits have recently grown and eats it, changing into an Evolved Form. Now stronger than ever, Demushu battles the remaining Riders on Earth and defeats them shortly after Duke left the Riders to die and the Kurokage Troopers is disbanded and before Kouta arrived. Kouta arrived to help the Riders and battles Demushu with a new power he received as Demushu witnesses Gaim's Ultimate Form as Kiwami Arms. Even though he's already more powerful, Demushu lost to Gaim Kiwami Arms' power and he was destroyed by Gaim Kiwami Arms' Hinawa Daidai Musou Zan.

Through an alteration to history rewritten by Shocker's History Modifying Machine, Demushu is among the many monsters that serve the evil organization that rules the world in this alternate timeline created by Kamen Rider 3's assassination of the Double Riders in 1973. During the final battle against the Kamen Riders, Demushu is destroyed by Gaim Orange Arms' Burai Kick, however, not before he (alongside several other kaijin) manage to kill Kamen Rider Mach.

Demushu becomes a member of Mu and fighting Kamen Rider Brain in Brain's dream.

Demushu makes an appearance in Kamen Rider Gaim: Final Stage. He is revived by Maja and helps subdue Kouta Kazuraba alongside his fellow Over Lords and the deceased, mind-controlled Armored Riders. When Kouta revives all of the fallen Armored Riders to his side, the battlefield becomes open warfare with the Riders, Maja, and the Over Lords all fighting. Demushu is later destroyed by Kaito.

Unlike Redyue, Demushu thirsted for power. He likes battle more than anything else. As shown, he was more of a musclebound brute than an intellectual, refusing to read a Japanese dictionary offered by Redyue and destroying another beforehand. He also wouldn't hold back and would pull out his full power towards his enemies.

Even when Kouta tried to talk with him, Demushu brutally attacked him. A bit similar to his human Rider counterpart from Earth, Kaito, he sees the weak as prey and doesn't deserve to be alive and he had the right to kill the weak to become the strongest of all. What he had already done was nothing but for his own satisfaction, making Kouta now see that there's no point talking with the Over Lords anymore. He also often referred to Humans as "Apes" and saw them as beneath him, viewing defeat or injury at the hands of Armored Riders as an insult and outrage to be beaten by them.

Over Lord

 * Brute Strength: Demushu possess incredible strength which made him strong enough to rip off a dictionary.
 * Durable Exoskeleton: Demushu's skin was covered with a durable exoskeleton that enable him to resist fatal injury.
 * Capacity Empowerment: Even after multiple times being defeated, his body would empowered to adapt into such fatal injury.
 * Vibration Manipulation: Demushu can generate and manipulate shockwaves and vibrations either in the form of projectiles, teleportation or super speed.
 * Helheim Plant Manipulation: Demushu can manipulate nearby Helheim vines for his own liking.

Arsenals

 * Sheimu (シェイム Shēimu): Demushu's personal sword.

Evolved

 * Brute Strength: Demushu possess incredible strength which made him strong enough to toss around multiple Armored Riders with ease.
 * Durable Exoskeleton: Demushu's body was covered with a durable exoskeleton that enable him to resist almost any injury.
 * Capacity Empowerment: Even after multiple times being defeated, his body would empowered to adapt into such fatal injury.
 * Vibration Manipulation: Demushu can generate and manipulate shockwaves and vibrations either in the form of projectiles, teleportation or super speed.
 * Helheim Plant Manipulation: Demushu can manipulate nearby Helheim vines for his own liking.
 * Attack Reversal: Thanks to the empowerment from his evolution, Demushu can turn an attack back on the attacker. As shown, he used his Sheimu to block the energy attacks of the Armored Riders and redirect the attacks back at them.
 * Fulgurkinesis: From the horns on his shoulders, Demushu can fire a red lightning attack.

Arsenals

 * Sheimu (シェイム Shēimu): Demushu's personal sword.

Trivia

 * TBA