During Kurama's attack on Konohagakure, some of its chakra was scattered throughout the village. Sora's father, Kazuma, collected the chakra, and sealed it into Sora's body, five years after the attack, to produce a partial copy of the Nine-Tails, turning Sora into a pseudo-jinchūriki. As a child, Sora's only known family was his father Kazuma, who he looked up to greatly and wanted to follow in his footsteps, later believing him to have been killed. After his father's presumed death, Sora went to live with the monks of the Fire Temple. At the temple, Sora trained hard in hopes of some day avenging his father and clearing his name, as Sora refused to believe what a horrible man people claimed him to be. One day, shortly after having Kurama's chakra sealed within him according to Kazuma, Sora went berserk, unleashed Kurama's chakra sealed within him, and destroyed the temple, a place otherwise believed to be an indestructible fortress. Afterwards, he was loathed by some of the monks of the temple, and soon began receiving the same ostracising treatment that Naruto Uzumaki experienced while he was young.
Sora attacked Naruto, who was separated from his team and stumbled upon one of the four hidden tombs they came to protect. When Sora was about to kill Naruto, Chiriku stopped him. After Chiriku stopped Sora and Naruto's battle and Sora gave information about the one of the four hidden tombs was stolen, he and Naruto started to argue each other, but were prevented from fighting by Chiriku and Yamato. After the confusion, they went to the Fire Temple.
Naruto found Sora sparring with other monks, and it seemed to him that Sora was despised, so he tried to befriend him, but was rejected. Sora, Naruto, and the rest of Team Yamato were soon sent to investigate a number of grave robbings of former members of the Twelve Guardian Ninja. Not interested in helping the team, Sora went off alone and found the enemy leader, Furido. When he discovered that he was their target, he questioned Furido about this, but started to grow angry when he received no reply. Furido taunted Sora until Sora unleashed his true powers, before informing him that he was planning to use the corpses to save the Land of Fire. After an explosion, Sora woke up only to find out that Furido had vanished, only leaving him a clue that he knew his father and that Sora resembled him.
Sora was assigned to go to Konoha with Team Yamato to replace an injured Sai. Naruto tried to show Sora around Konoha, but Sora went his own way, insulting those he came across. He later met Asuma, a man who had known his father and who offered to help him and Naruto with wind nature transformation training. Although he proved skilled with the Chakra Blades, he learned that Asuma was the one who had killed his father, something that caused him great distress.
Later on, Sora tried to look for Asuma, and followed him to Danzō's interrogation. There he found out that Homura Mitokado and Koharu Utatane disliked Sora, and considered him unwelcome in the village, planning to kill him. Before Tsunade could make her decision on what to do with Sora, however, he was discovered and captured by Anbu members. Enraged that he was hated even in Konoha, Sora attacked Asuma, his arm once again assuming a demonic form. Sora fled and sought out Furido, who told him that the only way to avenge his father was to kill Tsunade. When he failed during the initial attempt, he returned to Furido, who revealed himself as Kazuma and used the Five Elements Unseal to release all of the Nine-Tails' power sealed within Sora.
Before Sora could do any serious damage, however, he was confronted by Naruto. After recovering in the hospital, Sora bid farewell to Naruto and Team Yamato, asking them to tell Asuma he apologised for his actions before leaving to travel around the world.
We managed to harvest some of the Chakra that was expelled from the Nine Tails. It was tricky its Chakra couldn't be Sealed right away. It took us 5 years to implant it into the Boy we had Selected.
Chakra Enhanced Triple-Bladed Claw: This type of tekagi-shuko is a claw with three blades which can be enhanced with the user's chakra, even the user's chakra nature. It has the same effect as Asuma Sarutobi's trench knives. The original weapon that Sora wielded was broken in a battle with Kazuma. But due to an act of kindness from Asuma, it was later reforged with the same special material that was used to make his trench knives. During Naruto's confrontation with the four-tailed Sora, he uses a broken piece of the claw to injure himself in an attempt to prevent his own transformation.