Author's Note: Edited 2016-03-09 to fix error about Naruto already being told about her clan.
When they got back to their room, Hinata collapsed into her sleeping bag. Haku was locked in Inari's room with a chakra suppression seal on her. Inari would sleep with his mother. Naruto was feeling worn out, but she wanted to check a few things first. She pulled out a small mirror from her pack.
She activated her Byakugan and then increased the chakra to her eyes. The third eye on her forehead opened. It was red with a small black dot in the center and a single black tomoe rotating around the dot. 'Sharingan,' she thought to herself.
She tried to put chakra into her hair to move it, but she could not get the chakra to stay in it. Maybe she had to be angry to do it.
She put the mirror away and climbed into her sleeping bag. Sleep came quickly.
Naruto awoke on a gray, blasted landscape. Craters marked the land around her. The sky was open to the stars. Instead of the moon, she saw a much larger blue/brown/white orb up in the sky. A tall wall stood before her with a large gate made out of narrow bars in the center of it. On the gate hung a paper with the kanji for "seal" on it.
As she did not see anything else to do, she approached the gate.
"We meet at last, jailer," said a deep, masculine voice from within the gate. She could see only large eyes hovering in the darkness. She activated her Byakugan and saw a very intense fox-like silhouette with nine tails, containing several orders of magnitude more chakra than everyone in Konoha combined.
She looked at the cause of most of what was wrong with her life. She steeled herself. She was not going to give him the satisfaction of appearing scared or angry. "Kyuubi? Where are we? How did I get here?"
The Kyuubi ignored her questions and instead said, "So it is true. You look just like the pictures I've seen of her, except that you haven't mutilated your eyebrows and you bear my marks." He seemed pretty smug about the last part.
"Who? Outsutsuki Kaguya? Who was she?" Naruto asked. "That Zetsu thing mentioned that I felt like his mother, who was named that."
"I don't know who Zetsu is or was, but Outsutuski Kaguya created chakra by meddling in things she shouldn't have. She ate the forbidden fruit of the Shinju tree. Her son Hagoromo, known as the Rikudo Sennin, spread it and taught people how to use it hoping that it would bring people together in peace." He laughed bitterly. "He was a noble, if foolish, man."
"What happened to her?" asked Naruto. "There are legends about Rikudo Sennin-sama, but nothing about his mother."
This time the Kyuubi's laugh was malicious. "She went insane from the power. She decided that the only way the world would know peace was to trap everyone in a genjutsu—forcing a peaceful dream world upon everyone. Envious that her sons had inherited chakra from her, she merged with the Shinju tree and turned into the Juubi. Her sons defeated the thing she had become and Hagoromo sealed the Juubi into himself. Near the end of his life, Hogoromo split the chakra of the Juubi into the nine portions of various power, creating the bijuu. We consider him our father. He sealed the Juubi's body into the moon. So in a way, Kaguya was my grandmother and my mother."
"What does she have to do with me?" Naruto asked. "Why do I look like her?"
"I don't know the why—other than that you're her descendent—but I can tell you the what. People with unfinished business often leave some of their chakra behind. This chakra seeks out similar chakra—usually that of a descendant—and binds to it, influencing the development of the person whose chakra it cleaves to. The bigger the chakra, the greater the influence. This is called transmigration. In most cases the influence is small, but someone like Kaguya. . ." He trailed off. "No one knows if the transmigrant is like the original because of the lingering chakra or if the transmigrant attracts the lingering chakra because they are like the original. Probably some of both. Some people believe that transmigrants are the original person's soul reincarnated, but there is some evidence against it."
"What's that?" Naruto asked. She didn't like the idea that she was some crazy lady reborn.
"The two most commonly transmigrated people I know of are my father's human sons, Indra and Asura, the founders of the Uchiha and Senju lines, respectively. At least once, the transmigrants have called the spirits of their progenitors into this world to talk to them. Coincidentally, you are quite familiar with one of Indra's transmigrants, I can feel the stink of his chakra on you."
"Who is it?" she asked.
"Your Uchiha teammate. I can also tell that you've met Asura's transmigrant, but I don't know who it is, since I wasn't awake at the time."
"Am I doomed to go crazy, like your mother?" she asked, trying to keep the worry out of her voice.
The Kyuubi laughed. "Do you believe in fate, Little Rabbit?"
"No!" she shouted. "I'll make my own destiny."
"Then why worry? Asura and Indra's transmigrants act a lot like they did, but not exactly. Each time they transmigrate, their competition plays out differently. If it's any consolation, Kaguya was viewed as a benevolent goddess for much of her long life.
"To answer your original question, we're in a representation of your seal. It is connected to and mirrors your mindscape."
"Why does my mindscape look like a barren wasteland and what's the blue-moon thingy?" she asked.
"This place represents the moon and the blue orb above us is the earth. The connection to the moon you inherited from Kaguya."
"Why are you being so helpful?" she asked. "You're not what I imagined at all."
"I would like nothing more than to escape, Little Rabbit," he said.
"My name is Naruto, not Little Rabbit," she snarled, irritated at the condescension in the nickname.
"Ah, perhaps you are a fox in rabbit furs?" The fox laughed. "Very well, Naruto. Like I said, I would like to escape, but it's unlikely without your cooperation. I tried to influence you when your rage on the bridge summoned my chakra. However, since I was created out of Kaguya's chakra, your chakra contains an aspect that is very similar to my chakra and you can assimilate mine with very little effort. In light of that I would like to propose a partnership."
"Are you afraid I will absorb you like Zetsu?" she asked.
The fox chuckled. "The seal protects me from you, just as it does you from me. You might be able to absorb me, if you opened the seal. On the other hand, I might be able to escape when you opened it or you might burn out trying to absorb my incredible chakra reservoir. Are you willing to take the chance?"
"Before I agree to any partnership, I want to know why you attacked Konoha."
"In the days of your First Hokage, who was the previous Asura transmigrant, the Indra transmigrant, Uchiha Madara, thought to use me as his tool. He hypnotized me with his cursed Sharingan and sent me against his former friend. The Hokage's wife, Uzumaki Mito, used your clan's fuuinjutsu expertise to seal me inside herself."
"My clan were fuuinjutsu experts?" asked Naruto. "Why hasn't anyone told me?"
"I neither know nor care why you were never told of this.
"At the end of her life," the fox continued, "Mito sent for your mother, Uzumaki Kushina, to take her place as my jailer. This was right before Uzushio was destroyed."
"My mother!?" Naruto said excitedly. "What can you tell me about her?"
"Not much," admitted the Kyuubi. "She kept me chained inside her seal and it was rare that I became aware of the outside world. She had straight red hair and violet eyes. She looked much like you did before Kaguya's chakra awoke fully in you, other than her coloring. She was an excitable tomboy. That is all that I can tell you other than that her husband, your father, was Namikaze Minato, your Fourth Hokage."
"The Fourth was my father!? Why did he seal you inside me?"
"Again, I can't tell you much—other than the events that led to it," the Kyuubi said. "A female jinchuuriki's seal weakens while in childbirth. When you were being born, I tried to escape. Your father kept me locked inside the seal. A masked man with a single visible Sharingan kidnapped you and while your father was rescuing you, extracted me from your mother. He enslaved me with his cursed eye and made me attack your village, when I would have rather just have gone my own way. Your father sealed half of me into himself and half into you by summoning the Shinigami. Doing so cost him his life as the Shinigami dragged him and my yin half into its belly. Your mother died from a combination of childbirth, having me extracted—which is almost always fatal for the jinchuuriki, and being injured protecting you from me when I attacked to try and prevent being sealed again."
"So you don't know who the masked man was?" Naruto asked.
"No. Just that his eye was the mate of the Sharingan your sensei hides under his badge."
"What would this partnership entail?" asked Naruto.
"I will give you my chakra when you need it in exchange for access to your senses."
"That's it?" she asked.
"You have not idea how sick of looking at just this cell I am. The only consolation is that I'm not chained like your mother kept me. Perhaps later we can renegotiate if we come to trust each other."
"How would I do this?" she asked.
"Simply tear a corner of the seal. This will open the seal a small amount, allowing you and I greater access to each other."
Naruto hesitated. She was not sure if she could trust the fox. The mitigating factor was that she was able to absorb the fox's chakra on the bridge with no ill effects that she could tell. She thought that meant that the fox's ability to influence her was limited. In some respects, she also felt sorry for him.
"Okay, I'll do it. But if this is an attempt to escape or possess me, I'll give a try at absorbing you."
The fox snorted.
She walked closer to the gate and tore a small corner off the paper. She felt a surge of chakra, which subsided to a slight pressure which gradually became unnoticeable.
"You might notice a small degradation in your chakra control, but you have remarkably good chakra control for a human with your size of chakra reserves. It should not take much time to overcome."
"I hope this partnership works out for us both," said Naruto. "However, now I'm tired and want to sleep. How do I leave?"
"Simply will it," said the Kyuubi.
She did so and quickly fell asleep.