Kinkaku

was one of Kumogakure's Gold and Silver Brothers.

Background
The Gold and Silver Brothers were the most reviled criminals in the history of Kumogakure. Once, they were assigned to capture the Nine-Tailed Demon Fox, but were swallowed whole. However, they survived, and thrashed inside the tailed beast's stomach for two weeks, eventually forcing the Nine-Tails to regurgitate them. When in its stomach, they survived by eating the flesh of the beast. A portion of the Nine-Tails' chakra remained within them, giving them a large chakra reservoir, allowing them to use the five Treasured Tools of the Sage of the Six Paths without dying from the large chakra consumption. During the peace ceremony between the Second Hokage and the Second Raikage, the two brothers staged a coup d’état that left the Hokage on the brink of death. Sometime in his life, he met Kakuzu.

Appearance
Kinkaku was a burly shinobi, with a muscular build and towering stature. He seemingly possessed long, gold coloured hair with prominent dark tips, arranged in a style reminiscent of a Native American headdress. These features are accentuated by the presence of two distinctive horns that emerge from the abundant hair on his head as well as a light-coloured rectangular marking on his nose. Unusually, he had the same characteristic whisker-like marks on his face as Naruto Uzumaki.

His typical attire was comprised from the standard Kumogakure Flak Jacket, worn over a high collared sleeveless uniform, and a pair of simple wrist-guards. The kanji for is tattooed upon the shoulder of his exposed left arm.

Personality
Kinkaku was, like his brother, considered to be a disgrace to Kumogakure due to their belief of deceit and betrayal being battle strategies. Despite this, he is considered to be a loving brother, showing great fury when Ginkaku was sucked into the Benihisago by Darui.

Abilities
Kinkaku and his brother were well known for their prowess during their lifetime, so much so that one Kumogakure shinobi trembled in fear when he saw them and provoked the Fourth Raikage enough into almost disregarding his duties as leader of the Allied Shinobi Forces to personally confront the pair. According to Ao, the brothers both possess enormous chakra reserves with traces of the Nine-Tails' chakra mixed in due to being swallowed and regurgitated by the Nine-Tails after surviving two weeks inside its stomach.

Treasured Tools
The brothers wielded the five Treasured Tools of the Sage of the Six Paths, all of which cost a large amount of chakra, enough to kill normal humans before they can utilize the tools properly. The brothers can use them due to the combination of their high chakra level and the Nine-Tails' chakra. By combining the Benihisago, Kōkinjō and Shichiseiken, they can capture their opponent's and body, sealing them away for good. The Bashōsen allows them to create any of the five basic elements.

Jinchūriki Transformations
Despite not being an actual jinchūriki, he had absorbed a large amount of the Nine-Tails' chakra and ate some of its chakra flesh while trapped in its stomach. So much so, that he was able to enter a more muscular version of Naruto Uzumaki's six-tailed form with one tail vastly longer and thicker than the others. However, it lacks the Nine-Tails' skeleton. Kinkaku also retains his consciousness, unlike Naruto, who lost to his bestial instincts in this form, likely due to the absence of the beast itself, though rage still seems to be the trigger that makes him enter this form.

In this form, he is seen using his chakra tails to strike with great force and range, block a torrent of kunai with said tails, throw a giant rolling tank aside and easily break out of the Shadow Imitation Technique in seconds. However, despite its similarity to Naruto's higher forms, it seems to lack the corrosive chakra cloak that Naruto gains in Four-Tails and beyond.

Shinobi World War Arc
After his resurrection by Kabuto Yakushi, Kinkaku and Ginkaku are part of an Akatsuki coalition sent to the western coast of the Land of Lightning, where they are met by the First Division. As the confrontation commences, he recognizes Darui as the individual who inherited the Third Raikage's techniques, from the distinctive tattoo on his left shoulder, indicating to Kinkaku that he must be rather strong.

After Darui's comment, he says that, since years have passed, people from Kumogakure started to stop respecting him and his brother. After Atsui and Samui arrive, he summons from his mouth the Bashōsen and Shichiseiken, giving the latter weapon to his brother, and while the Kōkinjō wrapping in his right arm. He hits both Atsui and Samui with Kōkinjō and orders it to release their word souls so Shichiseiken can cut them. He then reads the special word from Shichiseiken and uses Bashōsen to burn Atsui's arm, forcing him to say, his special word, thus being sealed away. While his brother takes Samui hostage, Kinkaku attempts to attack Darui, but fails and Darui cuts his arm off. Darui then attacks both brothers with his Storm Release: Laser Circus technique freeing Samui in the same breath. Kinkaku however, kicks his severed arm with the Kōkinjō wrapped around it into Darui. He then cuts Darui's word soul and Ginkaku records it.

While Darui was being sucked into the Benihisago, he was able to change the word he used the most from to  inadvertently, thus cancelling the sealing technique. He disarmed Ginkaku, causing him to crash into Kinkaku and the Kōkinjō. Darui then commandeers both the Benihisago and the Shichiseiken, and proceeds to continue his onslaught on the brothers by launching his blade at Kinkaku who deflects the sword only to be bombarded with another one of Darui's attacks. Darui then uses this opportunity to curse and seal Ginkaku whose most used word was. Afterwards, Kinkaku went berserk, entering into his six-tailed form.

When in his six-tailed form, Darui said sorry for Ginkaku, but he responded it was too late. He caused havoc on the battlefield, killing many shinobi alone. After he saw the fifth treasure in Darui's possession, he guessed immediately that they were planning to seal him away. He almost kills Darui, but he's stopped by Kitsuchi's punch. Later, all the First Division and the reinforcements attacked him with a rain of kunai, which was easily repelled by one of his tails. However, it was a distraction so Chōji could attack him with his Human Bullet Tank. With his strength, he sends him away flying, but it was another distraction so Shikamaru could bind his shadow.

He breaks free with ease and tried to kill Shikamaru with one of his tails, but Ino used Mind Body Switch Technique on him, stopping him. Ino forced him to respond Darui's call, causing Kohaku no Jōhei to record his voice and start sealing him away after Ino switched back to her body. As Kinkaku is being sealed he laments how 'copper' people could defeat 'gold' and 'silver', Darui retorts that even though silver and gold may shine more than copper, a mass of copper coins can be worth more than one gold coin.

By nightfall, Tobi came and took the Benihisago and Kohaku no Jōhei, each with one of the brothers sealed inside it, with the intent of using their Nine-Tails chakra to put his Eye of the Moon Plan into action by the next day.

Trivia

 * literally means "Golden Horn", and shares the same name as the Kinkaku Force, suggesting that Kinkaku was its leader.
 * Both Kinkaku and his brother are likely based on two characters from the Chinese classic "Journey to the West". In this story, Kinkaku and Ginkaku are two demon king brothers, known as the and the.
 * Due to the brothers' ability to assimilate the Nine-Tails' chakra by eating its flesh, the Fourth Raikage suspected them to be distantly related to the Sage of the Six Paths.

Quotes

 * (To Darui) "Like they always say, 'silence is golden'. Words are the true source of all the world's ills… right Ginkaku?"