Power by accident: The Sharingan

Hyūga Hinata has been seen as the weakest clan member and a failure when she meets a mysterious dark-haired boy who is willing to help her.

A/N: This is a story part of my series, where I add some of the characters an additional power and see how it changes the world.

I am going to warn you already. Hinata is young but she is mentally sick due to childhood abuse by her family. Some of the events are not going to be healthy. Well, most of them to be exact.

My writing style usually includes a little situational humor, however, in this story this humor became a little... dark.. The story contains swearing, violence, and sexual situations. Nothing very explicit, though. You have been warned.

I have never before published any of my works, but I thought that if there is a chance that someone gets even a little joy of this, it is worth it. So try to enjoy!

Disclaimer: I don't own Naruto, characters or anything. This is just a hobby.

Part 1 – Only light in my darkness

6-year old Hyūga Hinata was a complete failure. She had known it already for a while, it was clear because of how everyone acted around her. Today, however, was the first time when it was said straight to her face. By her father no less. It wasn't a surprise after she had let Hanabi beat her in a battle because of her gentleness.

"Hinata. I am most disappointed with you. Today you showed me something I have known for a long time but never wanted to believe: you are a failure. I don't know what to do anymore. I have no choice but make Hanabi my successor. That means you will be going to the Shinobi Academy like a regular branch member. Now get out of my sight."

"Yes, father."

She was crying alone in the public training field far from the village. Not because she has to go to the Academy; that she waited, but because there were no one who believed she was unable to do anything. She started to hit a training post with an uncharacteristic fury which of course didn't help when using Jūken, but at least, it released some pressure.

She collapsed to the ground out of exhaustion. Her hands were sweaty and bruised. She watched the darkening sky through her half-lidded eyes. She wished she could just vanish so she wouldn't be on everyone's way. Think about Naruto-kun. He would never quit like this. He defended me against those bullies then, even if it was against all odds...

But he needed to defend you, you who has the ultimate eyes? How pathetic is that? The image of the blonde Uzumaki faded against a strong wave of desperation. She rose like a zombie.

"I am never going to be anything", she repeated out loud, not that she thought anyone was listening.

"Why do you think that?" asked a voice of a boy from the darkness of trees.

Hinata flinched. "W-who a-are you?" she asked timidly and fearfully.

"My name is not important. Answer my question."

An 11-year old boy with long, dark hair, fair skin, and charcoal eyes entered the clearing. He was wearing black and he was clearly a shinobi. He was currently giving Hinata his full attention and that made him the most beautiful creature in the universe in Hinata's socially starved mind.

Hinata looked ground feeling shame. "I am weak. My family and my teachers gave up on me because of that. I am the first main family member ever to go to the Shinobi Academy because of that."

He stared at her. The girl was six. The shinobi world was cruel indeed.

"Get up."

Hinata's eyes widened but she fumbled up and stood in front of him.

"Fight me."

Hinata hesitated.

"You don't want to waste your time fighting me..."

"Then defend yourself."

He attacked relentlessly. She activated her Byakugan and defended as much she could. He was good. He was a ninja of course, but as a Hyūga, she noticed that he was much better than an ordinary 11-year old should have been.

Their hands hit and kicks were blocked furiously. Both faces were focused on each other's. It all ended when Hinata made a mistake and gave him an obvious opening. She ended up against a tree and he held a kunai against her throat while she was panting harshly. She stared at the stranger's eyes fearlessly, still feeling adrenaline from the battle. It was a foreign situation for her since no one in the Hyūga compound ever sparred with a kunai.

"There are no major errors in your fighting. Your self-confidence and gentleness, however, affects your battle morale. I also see your physique is different from an average Hyūga. Jūken will never be your optimal fighting style."

Hinata stared in awe but her face fell when he finished. "So my father was right..."

He didn't answer.

Hinata turned to leave so she wouldn't bother him any further. She felt a hand on her shoulder.

"If you promise me to become strong, I will help you."

Hinata's desperate expression turned to a small smile. At that moment, she could have given that boy anything he asked, he had promised to make her worth something after all.

"I promise."

"Good. We will be meeting here a day after tomorrow at the same time. I believe it is not wise for you to advertise these meetings to your clan."

Hinata looked puzzled but nodded. He nodded as well and turned to leave.

"Wait...? Could you now tell me your name?" Hinata pleaded. It was weird to meet someone whose name you didn't know.

"Itachi. Uchiha, Itachi."

It felt familiar.

"Thank you, Itachi-sensei. My name is Hinata."

"Very well, Hinata-san."

They left to their own compounds, Itachi puzzled and Hinata pleased that there was one person in a world who noticed her and gave her his time.

"We will focus on taijutsu and the physical exercises for now since your chakra capacity is still very small. I believe your clan specializes in different chakra control techniques so you should utilize those on your own time."

Hinata watched him in awe. He was so much more beautiful than she remembered. And all those points he showed that never occurred to her.

Itachi continued: "I will teach you our clan taijutsu style which is all about speed and agility. You will, however, learn to combine it to your Jūken and direct most of the strikes to the tenketsu to maximize the damage to the internal organs. You must promise me that you will never use this style alone, I technically am not allowed to teach this."

Hinata was exhilarated. Itachi-sensei was breaking rules for her! She nodded and took her stance.

"Now, copy my movements."

Itachi was an active ninja of Konoha so he wasn't able to train her often, but he compensated that by giving her a lot of tips how to train by herself. So she trained like a madman. The promise to Itachi was giving her a motivation much higher than ever before in her life.

Her previous motivation – Uzumaki Naruto – had forgotten and replaced by her dark-haired sensei. He had become her obsession and to be honest her reason to live. She dreamed of Itachi, when she woke up she thought of him. His face was on her mind when she trained and he was the last thought in her mind when she fell asleep.

It was the first day of the Academy. She arrived there with her cousin Neji, who was at the Academy too. He snorted her and left her alone as soon as they arrived. She noticed many semi-known faces in a crowd, most were with their parents.

Naruto was there, the pink-haired girl she had seen in town every now and then, a boy with dark glasses, a boy with a pure white dog on his head... Her gaze stopped when she saw her sensei. She almost screamed with joy but stopped herself when she realized he was with his clansman: a smiling dark-haired boy in a shirt with a fan on the back. Was he Itachi's brother? They had never talked about their families. She suddenly realized how little she knew of him.

Itachi's eyes met Hinata's for a second. His expression didn't waver, but the intensity of his gaze told her he had noticed her. She felt delighted and watched intently him go. He turned and left the Academy with the other escorting family members while the new Academy students strolled inside the school building. The smaller Uchiha looked her direction looking slightly suspicious, but probably decided it was nothing and ran inside enthusiastically.

Their new sensei was a fresh chūnin called Umino Iruka. He seemed to be nice and a good teacher, who however had no time to Hinata since a couple of difficult students needed his attention more. So her minor mental problems were ignored and she became the student who was always there but never present. She was pretty sure most of the fellow students didn't even know she was there and this was ok for her.

Two of the students, however, noticed her – Uchiha Sasuke, as the Itachi's clansman turned out to be – clearly watched her regularly. It was expected as the Hyūga and the Uchiha had been rivaling clans for a long time. He never contacted her however since he mostly seemed to hang out with his nameless Uchiha cousin who was in the Academy too.

Another one who noticed her was Aburame Shino, the boy with the glasses. He never talked too much but kept her company during lunch breaks which she was thankful for. They were not friends exactly, more like allies, but it was better than nothing.

The first month in the Academy was over and she was rushing to her weekly meeting with Itachi smiling widely on that sunny Friday afternoon. She was fiddling some shurikens in her kunai pouch strapped on her left leg – they would train her projectiles today and she was absolutely thrilled.

She arrived their clearing only to notice Itachi passed out in the middle of what seemed a combination of exhaustion and a mild kunai wound. It was so hard to Hinata to remember that Itachi was still a child himself too by the way he acted and the way she saw him. It was horrible to see him bloodied and dead to the world. She started to clean his wounds and treat them with her home-made cream that she always carried with her and bandage him. After that, she moved him to the shadow of a tree.

Hinata would have wanted to take him to the hospital, but she was sure Itachi wouldn't have wanted her to take him there because of something this small. So she was waiting for him to wake up and started throwing shurikens while doing that.

It was already evening when she herself was too tired to continue. Itachi had yet to wake up so she sat beside him. Her tiredness however overcame and she soon fell asleep right next to him.

When he woke up it was already night. How long was he passed out? It was midday when he had started training. He noticed the bandages and soon after that sleeping Hinata next to him. He smiled, she looked very cute while sleeping. He observed the training ground which was full of shuriken marks like it had been raining them. So she trained herself. Very good, Hinata.

It was, however, a little tricky how to get her home. She was only 7 so she should have already been sleeping in her room and definitely not sleeping in the forest with 5 years older boy. Waking her up would only harm her so he decided that the simplest approach would be the best. He inserted his ANBU mask, raised her bridal style and carried her to the gates of Hyūga compound.

The Hyūga guards were a little astonished seeing an ANBU guard carrying their princess but when he explained that she was found on the training grounds after harsh training, they took her in without further questions. It was time for him to return to his clan compound too.

Hinata opened her eyes only to notice she was in her own room.

"So you are finally awake."

It was her father. This was bad. Hinata rose in her bed and turned to look at him impassively.

"Care to explain why were you carried to the compound by an ANBU guard after midnight?" Hiashi interrogated her not giving her time to wake up properly.

ANBU guard? They were those ninjas with masks. She had never seen Itachi wearing such attire, but she had to admit she didn't know if Itachi was one or not. Who else would have brought as insignificant a person as her home, though?

She decided to tell the truth... or part of it at least.

"I was training to exhaustion. Then I fell asleep", Hinata explained carefully waiting for her father's disappointment.

Hiashi seemed to have heard what he expected to hear since he rose to leave. "Very well. That sounds like a slight improvement. Don't get caught next time, though."

Hinata's eyes widened. It was almost a compliment. Too bad she only wanted those from Itachi these days. But still.

She hurried out of bed, ate breakfast in a hurry and rushed to their training grounds.

Itachi was there too. It was surprising since he usually had clan related duties on Saturdays. He looked as graceful as always and she watched in awe.

He finally noticed her staring and turned to smile at her. She rushed at him and launched herself at him hugging him tightly.

"Itachi Itachi Itachi..."

His eyes widened a little.

"Shhh, Hinata... I am here."

"I was so worried when you didn't wake up and I didn't know if I should have taken you to a hospital and what if you have died? You are the only light in my life, Itachi, and I cannot live without you..."

His eyes widened even more. Nobody had ever given such a confession to him. Sure he had some crazy fangirls, but none of them were actually meaning anything they said. He hugged her closer and let Hinata rest her head on his shoulder.

"You did very well Hinata and I am thankful. Did you got any problems at home?"

She shook her head.

"Father asked why I was carried home by ANBU guard and I told him I trained. He told me not to get caught next time", she explained.

"Good. I don't want you to be abused by your family ever again. I'm going to be with you somehow from this day on", he assured whispering to her ear.

There were tears in Hinata's eyes.

"Itachi! I am so happy I have you!"

"Me too Hinata, me too."

They trained today her projectiles just like they were supposed to a day ago.

It was about three months before Hinata's eighth birthday when she met Itachi (who had recently turned 13) on their training grounds as they normally did. She noticed right away that he was a little out of touch today so she went to ask him if she could help somehow. She hated to see her most important person sad.

He took her for a hug, which was special since usually it was normally her who hugged him first.

"Itachi? Is everything ok?" she asked concerned.

"Mmm. There are small troubles within the clan. Not anything you need to worry about, Hinata."

"Are you sure? I want to help so you can be happy."

"I am happy whenever I am with you, you know that" he smiled at her. She couldn't but smile back. His smile was absolutely perfect and the most beautiful thing she knew.

"Then you have nothing to be concerned about! I am going to be with you until we die!" Hinata declared, as eight-year-olds usually do to things.

His eyes widened. He had not got used to her blatant confessions of her affections at all during the two years they had spent training together. He knew that Hinata was very young but she was abnormally attached to him due to a childhood trauma. He himself was not very much healthier due expectations of his father and early career as a shinobi, which had made him attach himself to her as well.

"Hinata, I wish to protect you even if I cannot someday be there physically. Do you trust me Hinata?" he asked with a surprisingly steady voice.

"Hai, I trust you with my life."

"Good."

He brought up to pieces of paper with a peculiar design in them. He pressed one above his heart and other on Hinata. The identical figures appeared to their skin just above their hearts. He took a kunai and sliced their palms enough to bring up blood. Hinata watched wide-eyed but never complained.

He brought her palm to his heart and pressed his against hers. Hinata thought that this felt much more intimate than anything they had ever done before, but not distressing. They watched each other's eyes intently.

"Hinata, I wish to be with you until we die too."

Hinata gasped. "Itachi..."

"Channel some of your chakra to your palm Hinata..." he guided her as he did the same and formed half a hand seal with his other hand.

"Seal!"

The figures on their chests reacted to blood and chakra making Hinata gasp and faint. Itachi panted harshly but stayed conscious. The figures on their chests faded quickly. He brought her up, gave her a little kiss on her forehead and carried her to a training ground closer to town before rushing to his meeting with his cousin Shisui.

Hinata was found and woken up by a chūnin who guided her home. She told Hinata that she was Kurenai Yuhi and that she would help Hinata to train safely if she ever needed help. Hinata thought this was very nice.

The week in Academy went ok and on Friday, she rushed to their clearing to wait. Itachi, however, didn't show up so she practiced Itachi's taijutsu katas until the sky darkened. She went home and thought about Itachi even more than usual before she fell asleep.

Hinata was leaning her head on her desk while waiting for Iruka-sensei to start his lecture. It wasn't until Uchiha Sasuke stepped inside the classroom when the students started to gossip. Sasuke looked blank and annoyed and clearly didn't want to talk to anybody.

"Did you already hear? There was a massacre at the Uchiha compound last Friday night. Sasuke-kun was the only survivor."

"Oh, my Kami. That is horrible! Did they know who did it?"

"No. Is there anyone in the village even who would be powerful enough to murder a whole clan on one night?"

Hinata listened the rumors terrified. All the Uchihas are dead, except Sasuke... That means... She couldn't help herself but let an unidentified noise that was something between a scream and sob and escaped the classroom. She bumped on Iruka who was coming in but never apologized as she rushed out sobbing.

Sasuke watched at her incredulously.

"What happened to Hinata?" asked Iruka the class.

"We don't know. We were talking about the massacre and she became like that."

"Well, Hinata is from the Hyūga clan that is in many ways similar to the Uchiha. It could terrify anyone to realize it could have happened to them", Iruka analyzed. "Now, we will use some time today to discuss last Friday's events so there will not rise weird rumors or irrational fears about this. Does anyone has questions...?"

Hinata was sitting in the middle of their training grounds pressing her hand on her heart where she knew their seal was. Or had been. She didn't know if it was still there.

"Itachi..." she sobbed while trying to deal with his death. Had he known he was going to die? Hinata, I wish to protect you even if I cannot someday be there physically. That sounded like the seal was still there. That calmed Hinata down a lot.

Her motivation and the light of her darkness was gone, but she couldn't just give up. Itachi had told her he wanted to protect her and she couldn't let his work go vain. She needed to strive even harder to grow strong and let Itachi be proud of her in afterlife.

The only issue was his brother, Sasuke. Hinata had never liked him very much, but he was the same blood as Itachi and Itachi had clearly cared about him. There was only one course of action. She would dedicate her life to protect Sasuke. And so she swore hand on her seal that the last living Uchiha would live as long as there was air in her lungs.