Fū Yamanaka

was a shinobi from Konohagakure's Yamanaka clan as well as a high-ranking ninja of the disbanded Anbu faction: Root.

Background
In the anime, Fū was among many promising young children from various clans of Konohagakure that was personally selected and recruited by Danzō Shimura to join Root, much to the dismay of Inoichi Yamanaka. His training was directly under Danzō's supervision, alongside "Kinoe", a research subject of Orochimaru's who obtained a diluted Wood Release.

Later, already well-adjusted to the workings of Root, he was paired up with the newly recruited Torune. Despite some mild mocking on Fū's part, he was tasked with instructing Torune with the workings of Root. Ultimately, the two formed a strong and long-standing friendship.

Personality
Like all other members of the Anbu faction, Root, Fū lacks a personality due to the gruesome training regime Danzō had them undergo at a young age. As such, he acts merely as a tool that carries out Danzō's orders. The only discernible trait that he and the other members have shown is fierce loyalty towards Danzō. As such, he was willing to face Tobi with Torune and Danzō without fear or losing his temper, or even take his own eye out, while possessing Ao's body, calling it a "small price to pay" in order to fulfil Danzō's orders. In the anime, as a child, he was somewhat cocky and more cheerful. Despite the teachings of Root, Fū genuinely viewed Torune as a trusted friend.

Appearance
When first introduced, Fū's appearance was that of a regular Konoha Anbu, with a white cloak and mask. When he removed the mask, it was revealed that he was a young man with auburn coloured hair and amber eyes. He wore a short, black jacket with red straps on the shoulders like all members of Root which most likely shows allegiance to the organisation. He also wore a red short kimono under the jacket with a black sash, a pair of black gloves, dark-coloured pants, and regular shinobi sandals.

As a child in Root, he wore a light brown short kimono with a black sash, grey pants and shinobi sandals. Fū also wore black wristbands on his wrists.

Abilities
Danzō stated that he and Torune are two of the most-skilled ninja in Root. Fū also appears to be a skilled sensor, enough to detect Sasuke and Karin approaching the party gathered at the Kage Summit. His reflexes are fast enough that when Tobi reappeared, he instantly sensed him and counter-attacked. In the anime, Fū demonstrated as a child to be skilled in taijutsu, able to skilfully deflect Torune's attacks without being infected by his rinkaichū. As an Anbu, Fū is also versed in kenjutsu and carried a tantō, being capable of delivering quick slashes using it.

Yamanaka Clan Techniques
Fū is skilled in the use of the Yamanaka clan's various techniques. Aside from his use of the common Mind Body Switch Technique Fū displayed a versatile use by combining it with his trap making skills, developing cursed seal variant that allows him to transfer his consciousness into a strange scarecrow-like puppet with kama and kuwa for limbs. He proceeded to use the scarecrow to attack Ao. Although seemingly easily defeated, Ao then found that a secondary ability similar to a cursed seal had triggered a switch of his consciousness with the scarecrow. All the while, Fū was unconscious and being carried around by his partner, Torune.

Five Kage Summit
Danzō selected Fū and Torune to escort him to the Kage Summit in the Land of Iron. While on route there, they were ambushed by the Prajñā Group, but Fū and Torune stood down upon Danzō's orders as their leader wanted to exercise his skills. Once they arrived and the meeting began, Fū and his partner came to Danzō's defence during the Fourth Raikage's outburst and Zetsu's subsequent appearance. Zetsu informed them of Sasuke Uchiha's presence in the Land of Iron, and Fū alongside Torune tried to go and eliminate him but were unable to leave as Danzō, who had attempted to control Mifune was put under surveillance. Fū later alerted Danzō when Sasuke's sensor located them and subsequently fled with Danzō when Sasuke arrived at their location, but were pursued by Ao. At some point, Zetsu's Spore Technique activated while they fled, but they manage to free themselves from the spore-induced clones.

Danzō later instructed Fū to stop Ao, and retrieve or destroy the Byakugan that the Kiri-nin had in his eye socket. Fū laid several traps, including a cursed ragdoll, which attacked Ao, forcing the Kiri-nin to retaliate. This activated the curse and Ao became trapped in the puppet while Fū took control of Ao's body However in his attempt to remove the eye, Ao's seal decals were activated, and covered the eye. After trying to remove the tags with a kunai, Fū sensed the Fifth Mizukage and Chōjūrō coming and proceeded to bind Ao's hands and tie a kama to a tree branch, telling Ao that he was going to decapitate him so that he could simply take his head. He then jumped down towards the kama, but the Mizukage arrived in time to catch him. Acting as Ao, Fū explained that his body was being controlled, but apologised to her and Chōjūrō for worrying them and asks her to untie his hands. The Mizukage prepared to do so, while also offering to remove the seal from the Byakugan, to which Fū agreed, planning to crush Ao's eye as soon as this was done. However, the Mizukage left his hands bound, and asks Chōjūrō to lend her the Hiramekarei, explaining that the real Ao would have never apologised to Chōjūrō in such a manner, and that Ao also knew full-well that even she wasn't able to remove the seal over his eye. Fū then insulted the Mizukage for seeing through his deception before leaving Ao's body.

Returning to his body, Fū apologises as the mission ended in failure. Arriving at the Samurai Bridge, the group was ambushed by Tobi. While Danzō prepared for battle he has Fū and Torune distract Tobi in order to buy enough time to undo the Sealing Arm Braces. Fū tries to use the Mind Body Switch Technique, but Tobi phased through a pillar before he could cast the technique. Tobi staged a counter-attack and Fū slashed at him with his tantō, but Tobi caught the blade. Torune then threw a kunai at Tobi, forcing him to release Fū. Fū and Torune tried attacking from different angles, hoping that one of them would be able to attack Tobi while Tobi was attacking the other. However, Tobi saw through their plan but played along, causing Torune to accidentally infect Fū with his rinkaichū. Clutching his arm in pain, Torune extracted the bugs, and cured Fū, but before they can counter-attack Tobi quickly sent them both away with his space–time technique.

Fourth Shinobi World War: Confrontation
To alleviate some of his unease surrounding Kabuto Yakushi's motives, Tobi demanded that he demonstrate the Summoning: Impure World Reincarnation technique to him. Lacking the necessary sacrifices however, Tobi released the captive Fū, and Torune. Both mentally, and physically restrained, Torune was killed by Tobi, who then ordered that Fū be used to reincarnate the former. Obliging, Kabuto began the ritual whilst Fū remained motionless at the very centre of the ritual's seal. As ash and dirt begin to surround him, he cried out before both his body and soul are replaced by those of Torune.

Video Games
In Naruto Shippūden: Ultimate Ninja Storm Generations, Naruto Shippūden: Ultimate Ninja Storm 3 and Naruto Shippūden: Ultimate Ninja Storm Revolution, Fū is a support-only character.

Creation and Conception
Wanting a straight-laced, no-nonsense character, Kishimoto noted that it took some time to harden Fū's expression to what it is now. Because he is expressionless, the air of danger around him is even further accentuated. To this effect, Kishimoto noted that he then gave Fū powerful insight to bring out an air of deterrence. Earlier on in the conception stages, Kishimoto had Fū carry his mask strapped to his waist.

Trivia

 * Studio Pierrot's Settei sheets of Fū show that he was 152 cm tall when he was first partnered with Torune.