Prologue
"Ni-sama!" A voice cried as a young boy, only six years old, ran to the edge of the forest, gasping for breath as he tried to get away from the large bear chasing him. He had just wanted to do a harmless prank and thus ventured into the forest alone, not mindful of its many dangers. He was on the verge of collapsing from exhaustion when he felt his brothers chakra as he tackled the beast down from behind him.
Once he realised he was safe his fatigue caught up to him and he fell to the ground, breathing heavily, he was so so scared, his tears won't stop even if he tried.
"Asura? Ototo? Are you okay?" His elder brother asked gently, holding him in his arms, voice concerned.
"Yes, I-I was just-, Didn't expect to-" Asura broke into sobs in his brothers chest as he hugged him tightly. "Shh, don't you worry, Ni-san will always protect you" Indra smiled at his tear stricken face, a strong and comforting presence.
"You promise?" Young and hopeful eyes looked up at his elder brother with awe and adoration.
"I promise, rest, I will take us home" and with that Indra picked Asura up, who passed out from exhaustion in his arms.
----
For Indra Otsusuk, his younger brother was the most important thing in his life, he didn't know his mother, and his father loved them both, but he was the creator of Ninshu and had many duties that took up his attention and time. Indra didn't mind, always happy to shower his Ototo in attention. There was very little he wouldn't do for him. Indra was not a social person, he preferred to do things alone, he took upon everything by himself so that his younger brother could enjoy his childhood.
"Ni-sama, look at this, I did it all by myself" Asura says holding up a scroll of his Ninshu lessons left by their father. Indra turned to praise him and the young boy basked in his affection.
It was after their dog died and Indra met black Zetsu who spoke to him about power that he started withdrawing from his brother and father. He started using chakra for practical things and made hand seals to access it better. His father praised him and Asura looked at him with the same hero worship as in their childhood.
He awakened his Sharingan and spent most of his time creating new jutsus. Zetsu continued to fill his mind with ideas of power. Sometimes his brother seemed sad when they couldn't spend time together like they did before, but he reminded himself that all that he was doing was to keep Asura safe.
When their father was on their deathbed, they met their other siblings, the bijuu. Indra didn't really see them as family at first but Asura made friends with them all and so Indra accepted them as well, slowly coming to see them as his own little brothers. One night, after Asura had returned from his quest, his father declared him as the heir to Ninshu.
"Oto-sama! I can't possibly accept this, Ni-sama is elder and he is the one to develop most of the new techniques" he said to his father, but Hagoromo was firm in his decision. Asura watched as Indra left in rage, wanting to go after him but also wanting to give him space.
Indra felt disappointment anger for their father when Asura was chosen to succeed Ninshu. He had done all that he could so that his brother wouldn't have to worry about these things. He wandered into the forest, wanting to calm his mind when he met Zetsu again. He spoke of power and his potential, the unfairness shown to him by his own kin, and over some time his anger turned into hatred. The poison Zetsu filled his head with clouded the love he had for his family.
He and his two loyal followers returned home on the day his brother was being declared the heir. He killed them both and thanked them, for he awakened the Mangekyou Sharingan. Zetsu tells up about his prowess and how he can get even greater power. He attacks the celebration, denouncing the way of bringing peace by love and instead bringing it about with power.
Asura wants to join forces with his elder brother, and promises his father to never give up on his Ni-san as long as he lives. Hagoromo passes away and the two brothers continue to fight. Asura wants desperately for his aniki to make up with him but he can't let him hurt other people in their fights. So they both fight many battles over decades of their lives.
Once more they clash, and this time Asura knows is the last. They both fight with everything they have and Asura's heart breaks everytime his brother looks at him with hate instead of love. He wonders if he is going to die by the hands of his elder brother who looks at him as if he's the reason for all that's wrong in the world. A tear escapes his eye as he uses the last of his chakra to hit his brother, not being able to bring himself to hit a vital point. But Indra had no such worries as he dives his sword straight through Asura's chest.
Asura falls to the ground, his brother standing over him, a crazed glint in his eyes at finally proving power is superior to love. It is only when he looks at Asura's face that he sees his brother is crying, and Indra for the first time in years is able to separate his own thoughts from Zetsu's. He wanted to be strong so that he could protect Asura, his family. Over time he had forgotten the reason for always pushing himself to be the best. What use was a power if it took away the only person precious to him?
'kin-killer' a voice whispers in his mind and he jerks back as if slapped, because he couldn't kill his brother, but as he looks down at Asura's body which is slowly losing its life he realises it is him who did this.
"Asura!" He gasps, ignoring his own chakra exhaustion as he leans over his and tries to heal his wound. It is not working, he wasn't good at healing, he could only destroy. "Please, please don't die" he whispered as his own tears fall and he uses whatever bit of chakra he has to try and close the wound.
"Ni-sama...." Says Asura for the first time in years, because the person near him right now is whom he recognises as his beloved brother. Someone he hadn't seen for decades. "I forgive you" he says as his consciousness starts to fade.
"No! Asura, wake up, hang on please" Indra exclaims desperate as his brothers pulse weakens under his hands. He looks at his hands, covered in red by his own brothers blood, watches them shake as he falls beside him, his own energy running out. He knows that his wounds will bleed out, but that's okay.
"I promise Asura, even if I die, I will earn your forgiveness" he says as he closes his eyes and let's the world fade.
And so the two brothers reincarnate over and over, always with the purpose of solving their feud and earning forgiveness. But each time, Zetsu intervenes, and it is the same cycle of hatred and betrayal all over again.
There is one time when Asura's chakra is born attached to Hashirama and Indra's to Madara. Both of them are strong, closely to what Indra and Asura themselves had been. They both gravitate towards each other and dream about peace. Just like Asura, Hashirama wants everyone to live in harmony and end meaningless fighting, and just like Indra, Madara wants to keep his younger brother safe from wars and bloodshed. Asura and Indra believe that they may finally rest peace, but then Zetsu meddles and destroys everything, just like before.
Indra watches as Madara attacks to kill and Hashirama does to defend, he hates that this is familiar, hates that he let himself become obsessed and manipulated and his descendants do the same while his brother suffered every time.
But Indra is nothing if not stubborn, he will continue to try until he achieves his purpose and makes peace with his brother.
He watches as the years pass and his father becomes a legend and Ninshu is a word unknown to people. Ninjustsu is born and is used to fight rather than connect.
And then one day he meets a little eight year boy in their mindscape.
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Naruto is five years old when he sees someone in his dreams for the first time, the man tells him his name is Asura and tells him stories of his childhood and his brother. He listens to every word and enjoys their interactions because this person is always kind to him and no one is ever kind to him. For some reason, he can't talk back to the other person, only listen and express his words through gestures.
He looks forward to going to sleep more than the daytime which is when he is always alone.
----
Sasuke is eight years old when his brother kills his entire family, his entire clan, it is on that day that he swears to cut all bonds from his life and avenge his clan. It is also the first time he meets a man in his dream who calls himself Indra and tells him that revenge will only leave him hollow.