Night Rogue

Night Rogue is the leader of the enigmatic organization Faust and one of the main antagonists of Kamen Rider Build. His true identity is Gentoku Himuro, son of Touto Prime Minister Taizan Himuro and head of the Touto Institute of Advanced Matter Physics.

Past
Within a decade of the raising of the Skywall, Gentoku rose to a prominent position within the Touto government, being the one in charge of conducting research of the Pandora Box.

Seven years after the Skywall's emergence, Gentoku founded Faust along with researcher Takumi Katsuragi and Soichi Itsurugi, the astronaut who had caused the Skywall Disaster. Katsuragi designed the Transheat System for Gentoku to use to transform into Night Rogue.

Pursuit of Ryuga
Gentoku is first seen being interviewed along with his assistant, Nariaki Utsumi by Sawa Takigawa, where he states that the Institute's objective is to decipher the Pandora Box before other countries attempt to invade any of the three regions of Japan. The following day, Gentoku accepts Sento Kiryu into the Institute to assist in studying the Pandora Box. The two soon hear of the news that Ryuga Banjou has escaped from prison. Gentoku tells Sento that Ryuga murdered one of the Institute's researchers, Takumi Katsuragi.

Following Sento's battle with Strong Smash, Gentoku and an army of Touto Guardians and soldiers arrive and demand Build hand over Ryuga. However, Build chooses to instead escape with Ryuga, prompting the Touto forces to go after them.

Night Rogue later kidnapped Ryuga's fiance, Kasumi Ogura, to be turned into a Smash. When Ryuga called her, Night Rogue answered her phone and forced Ryuga to listen as Kasumi was prepared to be injected with Nebula Gas. Following Kasumi's conversion into the Burn Smash, Night Rogue unleashes the monster and sends it to attack Ryuga. With it being too late to save Kasumi due to her being a "Hazard Level 1", Build was forced to kill her to end her suffering.

Gentoku as Prime Minister
With his father falling ill, Gentoku assumed the position of acting Prime Minister of Touto. He met with Yoshiko Tajimi, the Prime Minister of Hokuto and Masakune Mido, the Prime Minister of Seito. At the meeting, Tajimi accused him of collaborating with Faust, but Gentoku replied by suggesting she has relations with Faust.

He was later approached by Blood Stalk, who demanded to know why Gentoku had placed the Pandora Box in an unknown location and not informed Stalk, but Gentoku told Stalk to act more loyal if he wanted Gentoku to reveal the Box's location. Their conversation was interrupted by two Touto security guards, whom Stalk killed effortlessly.

Stalk's Betrayal
Night Rogue later skirmished with Sento and Ryuga as they entered the Namba Heavy Industries Integrated Science Laboratory to find the Pandora Box. During the fight, Stalk interferes and attacks Night Rogue before locating the Pandora Box and teleporting away from it.

While Utsumi treats his wounds, Gentoku is approached by Faust's benefactor, Juzaburo Namba. Gentoku apologizes for letting the Box be stolen, and Namba forgives him, but states that countermeasures must be taken. The two decide to have the Touto government destroy Faust to remove any traces of evidence connecting them to it.

The following day, Gentoku stages a confrontation with Faust at a dam, with Gentoku leading the Touto forces while his assistant poses as Night Rogue. The imposter Night Rogue fights and is quickly defeated by Build KaizokuRessya. The defeat is picked up by the news, with Utsumi being forced out of his transformation and incriminated as the leader of Faust. Utsumi attempts to inform Build of something, but before he can finish speaking Gentoku shoots him and knocks him off the bridge and into the waters below.

Cover Blown
Meeting with Namba again, Gentoku is informed that Namba has found a new partner. He later contacts Blood Stalk and arranges a meeting with him. At the meeting, Gentoku attempts to get Blood Stalk to give up the Box's location. Blood Stalk agrees, but only if Gentoku swears loyalty to him. Gentoku refuses and transforms into Night Rogue to fight Blood Stalk and take the Box by force. Initially beating back Stalk, Night Rogue soon realizes that Stalk was holding back and is swiftly defeated by him. Stalk then reveals that he is Namba's new partner.

Gentoku later reveals to Sento and Ryuga that the Box is in one of Namba Heavy Industries' storage facilities, planning to have the two retrieve the box for him. However, after being exposed as Soichi Isurugi, Blood Stalk reveals that the true identity of Night Rogue is Gentoku Himuro.

After Sento and Ryuga succeed in recovering the Box, Gentoku sends a squad of Touto soldiers to break into nascita but they find no traces of the box. Gentoku later meets with Sento and Ryuga in the Touto Institute's parking lot, who reveal that they know Gentoku is Night Rogue and show him the box. After Gentoku reveals his plans to the Riders, Ryuga loses his temper and attacks Gentoku, who transforms into Night Rogue to fight him. Night Rogue manages to overpower both of them and recover the Box, only for it to be revealed to be a hologram, with the whole confrontation being a ruse to expose Night Rogue's true identity.

Defection to Seito
Gentoku's identity as Night Rogue and connections to Faust were later exposed to his father and the Touto government. Gentoku was ultimately forced to defect over to Seito, becoming their Kamen Rider as Kamen Rider Rogue. With his new power, Gentoku made an attempt to seize the Pandora Box as Taizan was having it moved to a new location.