Kimi Uchiha/Naruto Arashi

In Naruto Arashi, is a surviving member of Konoha's Uchiha Clan. She was a Genin-level kunoichi of Konohagakure for a short time prior to the Uchiha Clan Downfall, after which she ran away to Kumogakure, becoming a missing-nin.

Many years after, Kimi joined the organization known as Meiji under the pretense of both having the same goals of unifying the shinobi world.

Early Life
Kimi is the first and only daughter of Keiko Uchiha. Rumors said her father was a Senju, but this has been deemed false, since her father has been confirmed to be Fugaku Uchiha's brother.

Kimi graduated from Konoha's ninja academy at age 7 and was, alongside her genin teammates, immediately assigned a C-rank joint mission with a Kumogakure genin squad, Team Yugito, the joint mission being a sign of goodwill between the two villages. She was placed in the mission by the Third Hokage himself, as requested by her jōnin sensei, Aya Utsukushi. The mission details were to recover a scroll containing information about an ancient ninja weapon from an abandoned temple of a now extinct clan of assassin-nin, somewhere in the lands between the Land of Fire and the Land of Lightning. The scroll was to be handed to the mission's Kumogakure jōnin, Yugito Nii.

On the day of the mission, Kimi was accompanied by Keiko, her mother, to the village's gates to say goodbye, not knowing this would be the last time Kimi would see her mother alive.

The Mission
After joining up with the Kumo genin, the teams immediately started searching for the temple, and only took them a couple of days before they found it in the calculated location. However, a large local group of bandits had established it as their headquarters, and getting the scroll wouldn't be easy task. Yugito and Aya, the leading jōnin, preferred a more stealthy approach to having to fight all the bandits, as despite being ninja, most of them were still inexperienced children, not to mention the bandits severely outnumbered them. The group managed to enter unnoticed, with Kimi volunteering to dispose of the guards without raising alarm, which she so brilliantly succeeded at that it even impressed Yugito, but as the scroll was removed from its case, a secret alarm rang, withdrawing all the bandits' attention to the shinobi. The bandit chief somehow seemed to have knowledge of a strong fūinjutsu, which he used to seal the jōnin and stop them from helping the genin. After defeating several bandits, Kimi faced the bandit chief alone as the other genin held off other bandits, and managed to slay him by surprising him with a chakra infused kunai after being beaten head-on by the bandit chief, who claimed to have been a former ninja himself. With the user dead, the fūinjutsu restraining Yugito was released, the Jinchūriki then using Matatabi's powers to scare off the remaining bandits. It was after Kimi handing over the scroll that night as they set up camp, that Yugito expressed her amazement at the young girl's abilities, a true testament to the Uchiha clan's capability of producing such fine shinobi, and how she envied Aya for having Kimi as her disciple. Kimi thanked the kind words and returned to Konoha with her fellow Konoha-nin the following morning.

The Uchiha Massacre
Upon returning to the village at night, Kimi made her way to the Uchiha neighborhood, only to find its streets littered with corpses of fellow clansmen. Kimi couldn't believe what her eyes were seeing, so she slowly advanced through the body-ridden streets, until she came upon Sasuke's body. As if seeing her cousin lying on the floor still wasn't enough, immediately on a nearby corner was her mother's, however, she appeared to still be alive. Kimi ran to her, begging her not to leave her, but her mother could only answer that she should run as far from the village as possible to live and someday do what's best for her and the clan, in reply. Completely horrified at what was happening, Kimi then slowly turned around and started sprinting out of the village, tears streaming down her eyes.

As she was reaching the village's gates, she was intercepted by a Root shinobi claiming to be "moping" up after the Uchiha Clan killer. The shinobi unsheathed his tantō and swung at Kimi, who barely dodged his kenjutsu blows and managed to slip past him, making her way to the forest. However, the Root gave chase to her and stopped Kimi with Earth Release: Earth-Style Wall, who collided with the technique and fell helplessly to the ground. The Root made his way to her and prepared to end her life in a quick strike, but in the moment's desperation, Kimi awakened a two tomoe Sharingan that allowed her to dodge the attack and fatally wound her aggressor with a chakra-infused kunai. Even while dying, the Root still swung at Kimi, who easily dodged his clumsy attacks with her newly awakened Sharingan. After the shinobi finally collapsed, a distraught Kimi made up her mind to leave Konoha, seeing that she wasn't welcome there anymore. Kimi then remembered Yugito's words, and decided to travel to Kumogakure, using up all her mission pay on food and lodging.

Settling in Kumogakure
As she approached the village, Kumo ninja sentries attacked and captured her for interrogation. When asked about what she was doing there, Kimi said she just wanted to see lady Yugito, who was called at Kimi's request. The Jinchūriki immediately recognized the young Uchiha, who told her of what happened in Konoha and her situation. Yugito, as a Jinchūriki, knew the pain of loneliness and how it can crush a person, so she felt pity for Kimi and decided to take her in as her student, vowing to take responsibility and watching over her development, as such allowing Kimi to stay in Kumogakure.

Life in Kumogakure
For four years, Kimi trained under Yugito, honing her skill with her personal bukijutsu as well as her ninjutsu, particularly developing Wind Release, while improving her Fire Release. During this time, she lived in a guest room in Yugito's residence, and almost came to acknowledge her mentor as a second mother. It was also around this time Kimi met Len, who would become a close friend and develop a crush on her. Kimi also seemed to have taken an interest in kekkei genkai and techniques that could enhance her fighting style, as noted by Yugito due to the amount of scrolls about the matter in her room, and particularly kekkei tōta, which would later contribute to the development of her own kekkei tōta.

However, Kimi never forgot the horrid night of the Uchiha Massacre, and vowed to learn of the clan's killer identity and avenge her clan, as her mother's last wish. She would come to learn of it when Akatsuki members Kisame Hoshigaki and Itachi Uchiha came to Kumogakure to capture the Two-Tails's Jinchūriki. Kimi was shocked to see her cousin, believing herself to be the sole survivor of the clan. Itachi, much to his chagrin of having to kill another blood relative yet again, intended to finish the job for fear of retribution from Danzō's part on Sasuke, and revealed himself as the Uchiha clan's killer to Kimi through his Tsukuyomi. Enraged and heart-broken, Kimi finally decided to settle the score, and Itachi left Yugito to Kisame while he fought Kimi. Even while holding back, Itachi was too much for Kimi, who even awakened the third Sharingan tomoe on both her eyes during the battle; Yugito wasn't faring much better against Kisame either, and both were saved when Len, C and Darui arrived with backup, forcing Itachi and Kisame to retreat. Kimi promised she would one day take down Itachi, even if it meant years of arduous training. This would later spur her on to learn Nintaijutsu from the Raikage, as well as developing her trump card kekkei tōta.

Shortly after the incident, Kumo's elders blackmailed Kimi into working for the country as an assassin and spy if she wanted to keep living in the village, which Kimi accepted under the condition that she would be allowed to train with the A|Raikage in Nintaijutsu, a technique that sparked interest in her and wanted as part of her fighting style.

During three years, Kimi developed the Lightning Release nature along with several techniques for her bukijutsu, as well as starting developing her personal kekkei tōta, Energy Release, which was possible due to her three acquired natures and powerful Uchiha chakra, as well as her drive to become stronger in response to Itachi's words. She also earned her moniker, due to her unique fighting style combining the Sharingan with her Kōsōjutsu. Len, on the other hand, nicknamed her, claiming the blood of her victims that stained her Steel Claws disturbingly matched the color of her eyes.

Later on, Akatsuki once again attempted to capture Yugito, this time sending Hidan and Kakuzu for the job. After successfully taking down the jinchūriki, they stopped for Hidan's ritual. This gave enough time for Kimi to return from her mission and learn of what happened to her mentor. Kimi quickly gave chase to the two Akatsuki and managed to reach them in time (she reaches them before Zetsu takes Yugito in the manga, making him retreat until the fight is settled). Looking for a "real" sacrifice, Kimi was taken on by Hidan, and managed to hold her own against the Jashinist until Len came to help her, forcing Kakuzu to join the fight. Despite their combined efforts, and Kimi even managing to destroy one of Kakuzu's hearts with her new Kekkei Tōta, they were unable to overcome the immortal Akatsuki. Len was eventually marked by Hidan when he protected Kimi from one of his blows, and mortally wounded by Kimi herself when she attacked Hidan in his cursed state without knowing its voodoo-like effect. Immobile while grieving over her friend's death, Kimi was about to be struck down by Hidan as well when Killer B interfered in the nick of time. Zetsu lost his patience and took Yugito with him after telling Kakuzu and Hidan to "stop clowning around" and retreat. Failing to save her mentor and adding Len's death on top of it awakened Kimi's Mangekyō Sharingan and her Curse of Hatred, which would come to accentuate most of the darker aspects of her personality. After a brief talk with Killer B, Kimi left the village to pursue her own goals.

Naruto Arashi
So far, it is largely unknown what happened to Kimi after her defection from Kumo and the start of Naruto Arashi's timeline, although she claims to have obtained an Eternal Mangekyō Sharingan somewhere in between. This indicates she might have met yet another Uchiha survivor, of close-kin no less, and taken or given their own Mangekyō Sharingan. Sometime prior to the beginning of Naruto Arashi, Kimi joined the ranks of Meiji with the sole intent of fulfilling the organization's plans to unite the shinobi world under a single government.