Sora

is a monk that appears in the first filler arc of Shippūden. Sora also has the Nine-Tailed Demon Fox's chakra which was enhanced in him genetically which he has one arm of a Jinchūriki. Sora wanted revenge on Asuma Sarutobi for killing his father. Sora's name means "Sky" in Japanese.

Background
Not much is known about his childhood, only that he looked up to his father greatly and one day went berserk and wrecked the Temple of Fire, a place otherwise believed to be an indestructable fortress. Afterwards, he was loathed by some of the monks of the temple, and soon began receiving the same treatment as Naruto.

He wanted to become part of the Twelve Guardian Ninja. He hates himself because of his powers and gets angry when people stare at him. When he first met Naruto, they hated each other but eventually became friends. Sora does not like getting help from people, especially ninja. He did not even want Team Yamato to come.

Fire Temple Filler arc
Sora makes his first appearance in the tomb of a former Guardian Ninja. Due to a misunderstanding, Sora attacks Naruto Uzumaki and starts up a fight where he demonstrates rather proficient skill in wind-chakra based techniques. After the heated battle, the two are stopped by Yamato and Chiriku. After the confusion, the monks and Team Yamato travel to the Fire Temple.

Once there, Chiriku explains the situation to Team Yamato while Sora goes off to train. Naruto observes Sora sparring with other monks and becomes offended upon realizing he was holding back before. Naruto challenges Sora, but just as the matter is about to get serious, another monk stops him. Naruto realizes Sora is despised by the other monks as he was himself and wishes to befriend him. Naruto visits Sora again and observes him practicing his wind jutsu in earnest, hoping to get strong enough to avenge his father. They later return to the temple to receive news that another tomb has been robbed.

They are later ambushed by a group of enemy shinobi and Sora, unwilling to look for Naruto, goes off on his own. Sora then hits upon the enemy leader, Furido, and it is revealed that he is the group's target. Sora then starts to question Furido, but he does not answer. Instead he just sits down and roasts some potatoes. Sora gets angry and his chakra starts to get more powerful. Furido taunts Sora until Sora unleashes his true powers, before informing him that he is planning to use the four corpses to save the Land of Fire. After an explosion Sora wakes up only to find out that Furido had vanished, only leaving him a clue that he knows his father and that Sora resembles him.

Sora then is assigned to go to Konohagakure with Team Yamato to replace Sai because of Sai's injuries. Naruto tries to show Sora around Konoha but Sora goes his own way. Sora's insults precipitate a brawl with Kiba Inuzuka and Choji Akimichi, and Naruto and Rock Lee soon join in. Later, Asuma tells Sora he knew Sora's father, who is revealed as one of the Guardians involved in the coup attempt. He also shows Sora his chakra blade attack and then volunteers to help train Sora and Naruto.

Asuma supervises Naruto and Sora's wind chakra training, and notices that Sora, like Naruto, has very powerful chakra. Later, Asuma gives Sora a claw made from the same materials as his chakra blades. It is revealed that Asuma killed Sora's father Kazuma, who had planned to kill the Hokage. Furido then approaches Sora, telling him that Asuma is responsible for his father's death and passing him two "king" pieces from a Shogi set for Asuma. Shocked by this discovery he goes back to training distressed. Then Naruto approaches a furious Sora in the training grounds, who easily throws a chakra-powered kunai through a tree and destroys the stone behind it.

Later on Sora tries to look for Asuma and follows him to Danzo's interrogation. There he found out that Homura Mitokado and Koharu Utatane dislike Sora and don't welcome him in the village and plan to kill him. Before Tsunade can make her decision on what to do with Sora, he is caught by ANBU members hiding in the ceiling. Enraged, he yells at Tsunade asking her why would she kill him. Are his powers really that hated? He then goes on by saying that they are just like the fire temple monks. He looks at Yamato asking him, "are these what you call comrades?" He then changes his view towards Asuma and confronts him, accusing him of killing his father, which Asuma confirms. Sora attacks Asuma, his arm once again assuming a demonic form. While he blows Asuma outside, he is unable to maintain it for long, and falters. He is attacked by an unknown individual (presumed to be a Root shinobi), but Naruto shields him from the shuriken, being injured in the process. Sora then approaches Furido, who says that he must kill Asuma and Tsunade to avenge his father and consolidate the "two kings" (the Feudal Lord and the Hokage) into a single leader by eliminating the Hokage.

Later that night, Naruto catches Sora going after Tsunade. Sora retreats as Shizune and a few other ninja arrive, and Naruto pursues him. At that moment, a mysterious lightning storm strikes, cutting off power to the entire village. Meanwhile, Naruto chases Sora for attempting to kill Tsunade. Asuma, commanded by Tsunade to follow Sora and Naruto, finally catches up to them. Asuma realizes that the four invaders plan to annihilate the entire village using the lightning powers of the corpses that they stole. The revelation shocks Sora. As Asuma leaves to help hold off the attackers, he instructs Naruto to continue to pursue Sora.

Later on Furido tells Sora that when The Nine-Tailed Demon Fox rampaged around Konoha, The Fourth Hokage sealed the beast with in Naruto Uzumaki and the nine tails chakra that had slipped out when it rampaged was sealed it into Sora by Kazuma and the fire temple. He, Furido, then proceeds to use the Five Elements Unseal to release all of the demon fox's power. Sora grows a demon fox cloak similar to Naruto's, except that he has three spikes on each side of his face.

Like Naruto, he grows tails which increase in number the longer he keeps himself in the demon fox cloak state. If nine tails grow, he will turn into a real demon fox. However, Sora's jinchuriki powers are considerably weaker than that of Naruto's natural jinchuriki abilities. Later, as Asuma and Naruto arrive, it is revealed that Furido is actually Kazuma, Sora's father. A confrontation between Naruto and Sora later occurs, concluding with Sora losing control of his demon fox chakra. According to Captain Yamato, Sora's body did not have the proper capacity nor natural chakra reserves to contain the demon fox's chakra unlike Naruto, thus causing to Sora lose all of the demon fox's influence including the demon fox's chakra as well as Sora's Psuedo-Jinchuriki arm. After recovering in hospital Sora bids fairwell to Naruto and Team Yamato asks them to tell Asuma he apologizes for his actions before he leaves to travel the world.

Abilities
Sora is a wind-natured chakra user like Naruto. He is able to manipulate wind to form powerful gusts capable of lifting and pushing away man-sized objects or create chakra infused wind blades capable of cutting through most material and be directed by his will. The pinnacle of his wind-manipulation is to create a powerful claw composed of chakra-infused wind that he controls as an extension of his own arm.

He wields a tri-bladed death claw that he learns to infuse with chakra for a longer range of attack, which was refined further after training from from Asuma. Asuma gives him a new blade made of chakra-enhancing metal after his old one is destroyed in a fight with Furido. Sora is also a very proficient close-range fighter, as shown from his ability to defeat several of Naruto's clones, who uses a style of Taijutsu known only to the monks of the Fire Temple.

Also, like Naruto, he has shown to have high levels of stamina and chakra. Taking advantage of this, Sora's father Kazuma spliced his cellular make-up with excess chakra of the Nine-Tailed Demon Fox to create a Pseudo-Jinchūriki. Sora is capable, though unwillingly it seems, to transform into a miniature demon fox much like Naruto, but evidentally weaker than Naruto in comparison. In this form, he has all the power and resistance to injure and attack to the likes of an unsealed demon fox. After the battle with Naruto, all of Sora's demon chakra was expelled from his body, effectively taking away his ability to transform. The expelled chakra sought Naruto out as a host and thus, the whole of the nine-tail demon fox Kyuubi's chakra now rests in Naruto.

Trivia

 * Either because of an animation error or some kind rule in the Fire Temple, Sora was usually seen with white sleeves for his uniform but in some scenes they were black.
 * Sora's character seemed to be designed as a further example of wind-chakra.
 * Sora is quite popular with many fans despite being an anime-exclusive character.

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