Nariaki Utsumi

Nariaki Utsumi (内海 成彰) is the assistant of Gentoku Himuro at the Touto Institute of Advanced Matter Physics. He is also an aide to the Prime Minister of Touto and a former member of Faust.

He is later used as a decoy in order to hide the true identity of Night Rogue (ナイトローグ) during Touto's operation against Faust, before being gunned down by Gentoku himself. However, he was saved by Soichi Isurugi and is working with Namba Heavy Industries Ltd.

As the creator of the Kaiser System upgrade, Utsumi is able to use the Hell Bro's (ヘルブロス) form.

Character History
Utsumi is first seen reporting to Gentoku about Sento's application for a job at the Touto Institute of Advanced Matter Physics, noting that Sento had passed the entrance test with a perfect score.

Utsumi is Sento's direct superior at the Institute, reporting directly to the Prime Minister of Touto, Taizan Himuro, while at the same time also secretly assisting Gentoku/Night Rogue within Faust. He was one of the first present witnessing Taizan's collapse, after the Pandora Box was stolen from the Institute. The Box was later hidden within a secret basement at one of Namba Heavy Industries' laboratories.

Faust's Pandora Box Plan
Shortly after the emergence of a second Kamen Rider, Utsumi was called upon by Juzaburo Namba for a favor. Later, as he watched Sento return to work despite it being a day off for all lab staff, Utsumi decided to reveal the location of the Box's hidden location to Sento. Though, the Box ended up being reclaimed by Blood Stalk, and Utsumi was eventually forced to cooperate with Namba in his plan: to assume the identity of Night Rogue as a decoy in a staged operation by Touto to supposedly take down Faust. Due to Build's intervention, Utsumi was seemingly exposed as Faust's creator, though Build suspected that something was amiss.

Chased by Build to a bridge above a river, Utsumi, at his wits' end, confessed his inner troubles as a scientist. Revealing that he already knew that Build was Sento for a long time already, Utsumi urged Sento to not land into the same fate as his, and warned him to 'turn back' when he still have the time before he was shot in the shoulder by Gentoku, causing Utsumi to fall into the river below to his apparent demise.

Return


"It's been a while...Himuro."

- Utsumi's first word upon meeting a former superior

However, he survived and was pulled out of the river by Blood Stalk. He now works at Namba Heavy Industries and greeted his former superior, who was waiting for Juzaburo Namba.

Utsumi was approached by Gentoku, whom had been banished from Touto on his father's orders. Utsumi accepted Gentoku's request to be made into a Kamen Rider but not before taking pleasure in making him swallow his pride and beg for it.

On Stalk's orders, Utsumi went to Nascita where Sento Kiryu was surprised to see him alive as well as being able to make vastly superior coffee to Soichi Isurugi. Taking him underground, Utsumi revealed his intent to continue Sento's training to master the new Fullbottles left to him by Stalk in preparation for his deciding match against Kamen Rider Grease. Though Sento performed efficiently against simulated Smash Hazards with basic Best Matches, Utsumi pointed out that he would have to use the Hazard Trigger to defeat Grease. Sento understood this, and had already designed blueprints for a device which would cancel his transformation should he go berserk, but needed data of his Hazard Form's performance to complete it, to which Utsumi obliged by transforming into Night Rogue once more, using his self-made Transteam Gun from Gentoku Blueprint. Though he overwhelmed by SmaphoWolf Hazard as Build gone berserk, Utsumi was able to complete the dangerous procedure by using holographic Smashes to distract the rampaging Build, allowing him to forcefully pull out the Hazard Trigger and cancel Sento's transformation. With the data he needed collected, Sento was called away to intercept an attack on a Fullbottle facility.

Working on behalf of Namba, Utsumi updated the Kaiser System originally developed by the late Kaisei Mogami to create Remocon and Engine Bro's, which would be used by soldiers of Seito, Namba's prefered choice to inherit Japan. Utsumi was given the personal thanks of Seito's Prime Minister Masakuni Mido.

Personality
Nothing is much known about Utsumi's personality other than being a loyal assistant to Gentoku, even when his superior is revealed to be the leader of Faust and manipulating the Touto government from behind the scenes, as shown smirking whenever Gentoku, as Night Rogue fighting Blood Stalk. Though, he does seem slightly hesitant and reluctant at times as well.

It is later revealed that there is also a hidden depth to his personality, as Utsumi admits to Sento that they have a lot in common whenever they are trapped in unfitting situations they are in. He wanted to live a simple life as a scientist, though he admitted that he had lost his way as time passed, and warned Sento not to fall down the same path as him as a fellow scientist.

After being saved by Stalk and working with Namba, Utsumi seems to be more open-minded. He also faintly smiles after he finished the battle simulation with Sento. However, Utsumi proves to be more maniacal and ruthless, as demonstrated when Gentoku, after being exiled asked Utsumi to make him a Kamen Rider. He asks Gentoku to kneel, and by doing so, Utsumi steps on Gentoku's hand, reveling in sadistic laughter as he took his revenge for Gentoku's failed attempt to kill him.

Despite being employed under Juzaburo's (and by proxy, Soichi's) orders, Utsumi is easily unnerved by Stalk's murder of Mido, and Juzaburo going overboard of his ambitions of creating his Namba Empire with the power of the Pandora Tower.

Powers and Abilities

 * High Hazard Level: It is implied that Nariaki seems to have a high Hazard Level, due to his capability of using the Transteam Gun.
 * Genius-Level Intellect: Since Utsumi had worked for the Touto Institute, he possessed a certain level of intellect and this allows him to elevate to the rank of Gentoku's assistant. Because of this, Gentoku had speculated that Utsumi had a hand in the creation of Hokuto's Sclash Driver for Kamen Rider Grease, something which Sento Kiryu also suspected; this is later confirmed after Seito invades Hokuto, when it is revealed that Utsumi has built and upgraded another Sclash Driver for use by Kamen Rider Rogue, as well as duplicating Kaisei Mogami's Nebulasteam Gun for use by the Hell Bro's, all as part of Namba Heavy Industry's partnership with Seito. Utsumi also has access to data on some of Build's forms, including the Hazard and RabbitRabbit Forms, using them to Namba's advantage.

Devices

 * Transteam Gun - Night Rogue's transformation device and personal weapon
 * Bat Fullbottle - Night Rogue's tansformation trinket
 * Nebulasteam Gun - Hell Bro's transformation device and personal weapon
 * Gear Engine & Remocon - Hell Bro's transformation trinkets

Weapons

 * Steam Blade - Standard sidearm weapon. Can combine with the Transteam Gun to form the Steam Rifle.

Other

 * Tablet - While working under Faust, an by extension Namba, Utsumi is in possession of a tablet that allows him to create holographic Smash. The Smash holograms created by this device emit electric pulses upon contact, making them more realistic, hence they are suited for combat simulations.

Portrayal
Nariaki Utsumi is portrayed by Yuki Ochi (越智友己). His suit actor as Night Rogue is Jun Watanabe (渡辺淳).