Goddess of Ice; Reborn as Naruto's twin sister

The next few weeks really couldn't have gone any worse for Saido Kyarakuta. The day after he returned the test, a horde of angry parents arrived at school, demanding an explanation as to, why he told their children to stop becoming shinobis. Worst of all was that there were quite a few jonin in that group, which almost caused Saido to faint out of fear.

He didn't even know what he was supposed to say. He didn't remember saying something like that at all. It took him almost an hour to finally understand the whole story and when he did, he almost coughed out blood. Telling the heirs of 5 big clans that they should stop becoming shinobi certainly wasn't a good thing. He already felt quite lucky that he didn't "kill himself" with a few kunai in his back, last night. It took him a long time and a lot of begging until he managed to pacify the clan heads and convince them that someone was trying to mess with him.

If someone were to ask him what the worst part of the last few weeks was, he would only answer with a single word: Cake.

Every time he enters the class, a cake hits him in the face. He comes in while ducking? Cake. He opens the door, steps into the room, and then immediately jumps to the side? Cake. He jumps in through the window? Cake. For once, he didn't get hit when entering the class and sits down on his seat? Cake.

He was completely bewildered by it. He just couldn't get his head around how someone could predict his way of entry perfectly every day. He, of course, didn't understand that Yuna was the one controlling everything inside the classroom with the seal array she set up after her first day at the academy.

Yuna, naturally, had a goal in mind. Whenever Saido threw an insult at either Naruto, Hinata, or herself he would be hit by a cake the very next day. She wondered if she could condition him to have an urge to wash his face the moment she insults the trio. Or maybe something along the lines of: Wanting to eat a cake whenever he insulted them.

Yuna, on the other hand, had already lost interest in the academy. The last few weeks pretty much consisted of only loyalty classes, to make sure everyone is willing to fight to the death for Konoha. Yuna didn't condemn them for this. The best way to get soldiers loyal to yourself is by starting the conditioning early, after all.

Even in her previous life, stuff like that was pretty normal. The first thing everyone learns, as soon as they enter a cultivator sect, is how amazing that sect is and how advantageous it is to serve the sect.

Instead of putting much focus on the academy, she spent a lot of time inside the secret library that Minato told her about.

The house itself was left untouched for all these years. The barrier surrounding it was still standing when Yuna arrived. As someone who shared blood with both Minato and Kushina, she didn't even have to unlock the barrier, it just let her in. Since it seemed like a pretty decent place, Yuna searched for the core of the seals protecting the building and easily took control of it. It didn't even bother resisting her. She just had to drip a drop of blood onto it and she immediately got control.

She also noticed that there were a few attempts at breaking into the residence without anybody noticing. One doesn't need to be a genius to figure out who is responsible for that.

The library had a different set of protections, but with Minato's instructions it opened up just as easily. Unfortunately, the library didn't have much information about jutsus. Kushina always preferred to use the Uzumaki clan's Adamantine Sealing Chains in combination with her own seals, while Minato used the second Hokage's flying thunder god technique in combination with something he created himself: The Rasengan.

Unfortunately, the book only had a rough description of how the flying thunder god technique worked, since it was officially one of Konoha's S-Rank jutsu.

'Seriously, Minato, being loyal to the village is fine, but you could at least write down how the jutsu works for your children. Oh, well, At least I got the Rasengan.'

The Rasengan, however, turned out to be rather disappointing. Yuna just read through the instruction on how to master it and five minutes later, she had a blue sphere of chakra spinning around on top of her hand. Yuna spent quite a while every day honing her chakra control, so a jutsu that literally only needed chakra control was very easy for her to learn. For a moment, she had the urge to smash the blue glowing ball of chakra into something to see how powerful it was, but she suppressed it for now. She had to find out how strong it actually was when she wasn't inside a library.

After finishing the scroll, she was currently reading, she picked up the next one and instantly got curious about it. The scroll was simply labeled as "Kekkei Genkai". Yuna, naturally already knew what this was. It was basically a mutation that allowed someone to use techniques that should be impossible to use. So far, the only ones she had seen were the Sharingan and the Byakugan, but she also knew that there were people that could use chakra natures that actually don't exist. This actually includes ice, which she has tried to recreate for years now, but no matter how she manipulates her chakra, the result is always the same. No matter what she does, it always ends as one of the five chakra elements, Yin, Yang, or without nature. No matter what she tried, she just couldn't create ice chakra.

Yuna casually started to read the scroll, not expecting too much from it, but as soon as she finished reading the first sentence, she dropped the scroll out of shock: "A Kekkei Genkai means, that someone has a mutation in their genes that allows them to use two chakra nature at once, combining them into one."

'Are you telling me I just need to combine chakra natures to get something else? What kind of weird game of Mix and Match is this?'

Yuna didn't even bother to finish reading the introduction, she immediately started to skip through the scroll, to find what she was looking for. A few seconds later, she found it. The information she was looking for since she was reborn: Water+Wind=Ice.

The moment she got that information she got up and left the house. She was rather happy that it was the start of the weekend, so she had a lot of time to experiment. She quickly returned home and only left a piece of paper on the table stating that she won't be home during the weekend.

She quickly made her way towards one of the training grounds and as soon as she arrived her hands lit up with chakra and she started to carve a complex array of seals into the air. This array will prevent her from getting disturbed during her experiments.

As soon as she finished the seal array, she sat down crossed-legged in the middle of it and started to calm her mind.

Yuna lifted her right hand and caused a blob of water chakra to appear on it. While attempting to regain her control over ice, Yuna spent quite a lot of time messing around with water elemental chakra. She felt like it was the element that was the closest to ice, so it became her strongest element.

Then, Yuna lifted her left hand and generated a mote of wind chakra. Although she wasn't as proficient with it as with water chakra it was still her second-best element simply because fire, earth, and lighting don't really fit into her image of ice.

Then she lifted both her hands and started to slowly push the two chakra types into each other. The reactions were just as she expected them to be, the two chakra natures repelled each other making it seemingly impossible to fuse them. Yuna, however, didn't mind that at all.

'The first step towards doing the impossible is always a complete failure. If it wasn't, people might think that it was possible to do it, after all.'

For a split second, a smile filled with insanity and pure glee appeared on Yuna's face, just to disappear and be replaced with an emotionless face, that only showed deep concentration.

'Finally, a path to regain control over MY ice.'