Mito looked at her brother leaving and felt heartache, the truth is that she never hated Naruto, or wanted to act cold toward him, But because of one stupid time that she has listened to a stupid fox, she hurt her beloved older brother
Flashback -
*9 Years ago*
Young Mito was in her room, arguing with Narumi, both of them were fighting who will spend the day with Naruto. They didn't like to be together with him because every time one of them was close to him a bit too much the other will get jealous. So they decide they will share the time with him that every time one will get a private time to get spoiled by Naruto. Of course, Naruto had no idea
A heavy voice suddenly resounded in the room "Shut up brats I'm trying to sleep!" Both Mito and Narumi got scared, the voice sounded angry and full of malicious intent.
"Who is that Mito?" asked the scared Narumi.
"Well, if you wanna know, I will show you." The voice replied and with that, some red chakra came out of Mito, and before they could even scream they found themselves in a dark place.
The place seems like a prison, it was completely black, the walls seem like they were made from metal, In the middle, there was a huge cage, in the middle of it there was a paper with the word "Seal".
"Mito, can it be...?" asked the fearful Narumi that was with her elder sister.
"Yes. I think we are in the Kyuubi seal," answers Mito that seems to have a bit more courage.
"So you finally decide to show me some company?" The deep and heavy voice once again sounded, but this time it was clear, it came from the cage.
"Are you the Kyuubi?" before she could finish her question a pair of deep red eyes appear from the cage? These eyes seem like they wished to tear apart the two young girls.
"Yes, I am. The great nine-tail Fox, Kyuubi. You can call me however you want, but I prefer the first one. " Said the fox from behind the bars.
Neither Mito nor Narumi answered. They felt fear to answer to the monster in the cage. Neither Narumi norr Mito was the cowards, but they were still young girls.
"Young girl, who about coming closer to her, so we can get to know each other," Said the Kyubbi from behind the cage." with a grin.
But both Mito and Narumi were too afraid to get close and even if they wanted to they felt completely paralyzed.
"Stop looking so fearful. I feel sad if my carrier would be so pathetic. This jail, keeping me from harming you in any way." He said as he hoisted the bars.
"What do you want?" asked Mito, trying to overcome a bit of her fear, despite being a child she was smart.
"Oh, it seems like you gathered a bit of courage." He said with a grin. "Alright, I will tell you, you are in danger tomato girl."
"Huh? Who are you calling tomato?!" Mito yell, she wasn't hot-headed but just like her mother, this nickname has been something that she hated.
The Kyuubi chuckled a bit and thought 'Bingo.' and continued "Listen brat, you are in danger, usually I wouldn't care at all, but this time it's including my own life so I can't ignore the situation."
He said with a deep sigh and continued while looking at Mito and Narumi "You are my career, together with your siblings, all of you hold part of me, that's mean all of you are a target of extremely troublesome man, his name Uchiha Madara."
"Does he aim for us because of you?" Narumi asked with a furrowed brow. The Kyuubi answered "Yes. Do you think you worth his time otherwise?"
"Alright. Soon I will start to train with mom and dad, I'll face him, and with Menma and Narumi we will beat him up!" answered Mito with resolution and Narumi nodded her head in agreement!
Seeing their self-confidence the Kyuubi felt like he needs to wake them up "Alright to brats, let me tell you honestly, you won't be able to defeat Madara in the way you are now."
"What do you mean, I know that I'm not strong now, but soon we will start to train with mom and dad and even the three legendary Sannin! We will become very strong!" Narumi's intense eyes and resolution were very clear in her eyes when she said these words!
Seeing the resolution in Narumi's eyes the Kyubbi grind and said "True. You are the daughters of that Yondaime Hokage, and with how much I dislike him, he is very strong and with the support of these three sanins, you will become very strong. But not enough!" His tone changed to the seriousness that made the two young girl's hearts skip a bit.
"The thing that will hold both of you back is that the older brother of yours! You are both too attached to him! That useless love of yours to that useless kid will hold back your training and achievements!" He claimed. The Kyuubi wasn't the most pleasant, but he knew that these two had great potential to become amazingly strong, and with so much support, they will become as strong if not stronger than the three Sannin!
Narumi's face instantly grows a fit of anger and Mito shouted "Naruto-nii has nothing to do with it! He doesn't have your chakra in him! This Madara has no reason to go after him!" The Kyuubi wasn't fazed at all by that and merely said "Madara won't care about that, if he can use him to threaten you then he will do it. You two are too close to him, I can already tell that in the future you both will be skipping training to spend time with him, and this is unacceptable!" He said with a shout of anger that terrified both of the girls.
The Kyuubi stopped for a moment, realizing that they are still just kids, and said "This for his good. If Madara will ever target you or anyone from your family or friends, he will do it to someone worth threatening you. That brother of yours, Menma already realized it, If you two will distance yourself from him, then he will be in less of a danger."
Said the Kyuubi. What he said was completely baseless and untrue, but for a child and especially for girls that loved their brother more than they loved themselves that sounded very real.
Both Mito and Narumi didn't know what to say. They couldn't bring themselves to part with him for half a day, let alone to completely cut him off from their lives.
Their reaction was something that the Kyuubi completely foresee, despite not liking the way he did it, he had no choice both of them were completely shaken and it's a perfect time to hit the iron when it's still hot.
"You two want to protect your brother, then the best way to do it is to leave him behind. For once in your life don't think about yourselves, think about him." He said in the gentlest tone he could muster.
Mito looked at Narumi with a sad expression and said "What should we do? Narumi..." Narumi had a tear in her eyes and said: "We will do anything to protect Naruto-nii."