"I hate the cold," Naruto complained, despite the enchanted and rune-inscribed clothes he was wearing.
That January in the north of the Land of Fire was colder than usual. Surprisingly, Jiraiya hadn't left for work in almost three weeks, so he had decided to finally teach them something they had been asking about for months: fuinjutsu.
"Stop complaining, Naruto. Pay attention. I'm going to explain the basics of fuinjutsu now, so I don't want any distractions, got it?"
"Yeah, yeah!"
Sitting on a log, Jiraiya began explaining which kind of ink to use for specific sealing work. The symmetry of well-known barriers, how kanji were chained together based on his own experience, and more. Seina realized it was even easier than runes. After all, runes required anchoring to something, while fuinjutsu could even be written in the air, as her late father apparently knew how to do.
"So fuinjutsu is basically just a combination of structure, chakra, and kanji, right?" she asked after listening to him speak for nearly two hours.
"You could say that. Remember, what we non-Uzumaki know about fuinjutsu, we've often deduced from your clan's seals, so there might be protocols we still haven't discovered."
Something told her Jiraiya was absolutely right, and yet, she also had the strange feeling that such knowledge was hidden in the secret Uzumaki chamber in Uzushiogakure—a chamber only her team knew existed and that she couldn't access because, ironically, it was protected by an extremely powerful fuinjutsu she didn't know how to decode.
"I think we need to start reading those scrolls we took from Uzushiogakure," she told Naruto and Sasuke when she invited them to her room that night. "I'd say the pervert is right. We could make more progress if we had the theoretical knowledge of fuinjutsu."
"And you think those scrolls could help us?"
"Hn. In that case, I should go."
"Why?" Naruto asked.
"He says that because they're Uzumaki clan scrolls," she explained briefly. Then she looked at Sasuke and lifted the Uchiha bracelet he had given her. "You're my brother in everything but blood. I'm willing to show you these scrolls if you promise that only you, Sasuke Uchiha, will use that knowledge."
"And you, Naruto?" Sasuke asked with a serious expression.
"…You're a bastard, but I trust you."
"Alright. I promise to take that knowledge to the grave."
"Great," she smiled.
She caught a glimpse of Sasuke's more relaxed expression when he realized Naruto had accepted him, just like she had, without question. She pulled out the scrolls she had stored in her pouch, knowing it would take a while to find the ones at the right level. And so, they spent their time that way.
"Look at this one. It's about barrier creation, but it has explanations," Sasuke said a while later.
"And I found one with diagrams."
By midnight, they had a small pile of books and scrolls that contained some sort of explanation or interesting theory.
"We should leave it for tomorrow," she yawned.
"I want to show you something first," Sasuke interrupted suddenly.
He pulled out a medium-sized wooden tablet from his pouch, engraved with carved symbols. Naruto and she watched curiously to see what he wanted to show them. He placed the object on the bed next to the scrolls, and as soon as Seina laid eyes on the first sentence, she knew what it was. It was the Uchiha's sacred stone tablet.
"This is…!"
"It's a replica of the stone tablet located in a secret place in Uchiha territory."
"And you don't mind us reading it?" Naruto asked, also serious. "I mean… isn't this a clan secret?"
"Yes, but like you said, I trust you. I know you'll keep the secret. Besides… not even this replica is complete. I took it because it explains how to develop the next stage of my Sharingan."
"The Mangekyō Sharingan?" she asked, knowing that Kakashi could activate it, though he never seemed to train with it or use it in battle—at least not when she was around.
"That's right. That Sharingan is much more powerful than the regular one."
"And how is it activated?"
"That's one of its downsides," Sasuke admitted with a sigh. "To activate it, the user must witness the loss of someone they love after already awakening the Sharingan."
"…"
Sasuke looked at them both with a raised eyebrow.
"You two are the most unpredictable people I know, so I'd like to hear your opinion. Do you think I could activate it without you… dying?"
"Would a genjutsu count?" she asked.
"A genjutsu?" Sasuke blinked in confusion.
"I mean, if we manipulate your brain into believing we're dead… it could work, right? Or do you really have to see our actual death?"
"Huh. We could try that."
"And with your legilimency, nee-chan? You could try triggering the Mangekyō Sharingan from inside his mind."
"That's another option. I could also create a golem and kill it."
"What's a golem?"
"It's like a clone, but made of flesh and blood. It takes longer to prepare, but it can 'die.' Maybe that would be enough to activate your new Sharingan form."
Sasuke remained silent, nodding as he thought it through.
"I'd like us to try it."
"Alright. Leave it to me," she said, "and try to forget about it."
The more it caught him off guard, the better. That ended the discussion, and each of them went to their rooms for the night. Seina lay in bed, thinking about Sasuke's problem. An idea was starting to form...
The next day, they began practicing the fuinjutsu barriers Jiraiya knew. Meanwhile, her clones in her room began memorizing and internalizing the content of the scrolls they had separated. She knew she wasn't the only one doing this, since she had given copies to both Naruto and Sasuke so they could do the same.
After a few days, Jiraiya began to question how they were progressing so quickly.
"Since when do you know how to modify a barrier?" he asked aloud, squinting at them suspiciously. "You're not experimenting on your own, are you?"
"No," she laughed softly. "This is the first time we've tried it."
"Take a break while I review the modifications."
Seina, however, kept training with her adamantine chains. She had reached the highest level of mastery with three of them since she had started training two to three hours a day months ago. Now she was trying to control one more. She knew her limit seemed to be thirteen chains. Coincidence or fate? Thirteen, after seven, was a powerful magical number. She had a lot of work ahead.
"rasengan!" Naruto shouted to boost himself, but his rasengan didn't fly.
"I told you it's impossible to launch it without it falling apart," Jiraiya muttered, his face buried in a scroll.
"There has to be some way!"
"You still haven't figured it out, you blockhead?"
"Are you going to help me or what!?"
"No. I want you to think it through yourself. Seina, Sasuke, don't help him."
Seina rolled her eyes. The truth was, it had taken her a few days to realize what the pervert was hinting at—because it hadn't occurred to her to modify a jutsu she already knew, rather than creating one from scratch like she did with her corrosive/boiling water stream. If Naruto applied wind nature to the rasengan, he could probably launch it the way he was trying to—without adding any other chakra. That made her realize she could, in fact, modify all the ninjutsu she had already learned.
Saying she was too lazy to do it would have been a huge understatement. The only one who seemed interested was Sasuke. Honestly, she already knew so many ninjutsu techniques that she had one for every situation, so she didn't need to tinker with something that already worked perfectly. Not to mention she had her magic.
Kurama was the one who completely derailed her plans—with a simple question.
"Why do you need to use 'spells' to use your magic?" he asked curiously as he listened to her thinking about how to improve the rasengan. "You often use magic without casting a spell, so I know you can use your kekkei genkai at will."
"Because spells are thought-out formulas, and they always work correctly if the wand movements and pronunciation are perfect."
"But you never use verbal spells. Ever. Or a wand."
"But I think them mentally, and I've practiced enough to stop using a wand."
"Not always," Kurama pointed out. "I've noticed that with some spells you don't even have to think about them."
"…Really? Like which ones?"
"The summoning spell, the one for faint light, your transformations and conjurations—all without enchantments. Even your face-changing spells, you cast them this way. Maybe others too."
Seina was shocked to hear that. She replayed her memories and realized Kurama was right. When she looked at the list of spells she supposedly cast without thinking, she saw they were the ones she had used the most in her previous life. Want something from the room? She summoned it. Needed to go unnoticed on the street? She changed her face. Needed a seat, utensils, or a tissue? She conjured it without thinking or transformed something nearby.
That meant if she could cast those spells without consciously thinking of the spell… why did she need to use spell names at all? She had become institutionalized without even realizing it. Accidental magic was the purest form of magic, since children didn't know spells but could still use magic—usually in moments of intense desire or stress. So why did she need to know the name and the wand movement? She had discarded the use of wands years ago, and even abandoned speaking spells out loud because it was too dangerous as an Auror. Could she now let go of spellcasting entirely and just… use magic however she wanted? After all, magic was just a matter of power, will, and imagination.
"I need to train to use magic without relying on incantations. That would give me even more options than I already have. You're a genius, Kurama."
"I know," he answered smugly.
As if she didn't already have enough on her plate—learning new ninjutsu, inventing more genjutsu, improving her taijutsu and kenjutsu, mastering the adamantine chains, learning fuinjutsu from scratch, and studying those Uzushiogakure scrolls—now she also had to relearn how to use magic without spells. Ugh. Just thinking about it made her tired, but she knew that if she could manage it, she'd become even more unstoppable. And when would she ever get another golden opportunity to train without distractions or missions? Never again.
So the next day, she began practicing spell effects without saying or even thinking the spell. It wasn't easy—not even with over a hundred years of magical experience. She stared intently at the pedestal she had conjured and at the branches on top of it, which she intended to ignite using only her willpower. It was harder than it looked, because her mind kept trying to think of the Incendio spell, knowing it was the correct one to light those branches. She had to use mental barriers to block the thought, but that only left her mind blank.
"What are you doing?" Naruto asked as he approached from behind.
"I'm trying to learn to use magic without thinking of the spells."
"Seriously? Can you really do that?"
"Actually, I've already been doing it without realizing it—but only with the spells I've used so often they're second nature."
"So you don't have to think about them?"
"Exactly. I'm trying to set those branches on fire with my mind, without thinking of the spell, but it's hard because my brain keeps wanting to remember the words."
"I see... So why don't you just picture it in your mind?"
"What do you mean?" she asked, turning around and pausing what she was doing.
"When you conjure or transform something… don't you imagine what you're turning it into? Maybe that's why you don't need to say the spell."
Seina was stunned. Could it be that Naruto was right? Practically all the spells she could perform without chanting required her to visualize them first. In fact, visualization was one of the key elements of magic. Maybe Naruto was right! She turned again to look at the branches and, instead of thinking about the spell, she imagined the branches catching fire. Suddenly, that's exactly what happened. She took a breath and then imagined the fire going out. It took her a couple of tries, but it worked.
Discovering that she could retrain her magic, just as Kurama had suggested, raised a lot of questions in her mind. For starters, could she hold, say, a fireball in her hand just by imagining it? Would it burn her if she kept it in her hand? Or could she, like with some complete jutsus, shield her hand from being burned? Kakashi and Sasuke's chidori were incomplete jutsus—especially Sasuke's—because they didn't know how to protect themselves from the lightning running through their own arms.
What would happen if, instead of a fireball, she tried to conjure the killing curse in her hand? Would she die just by touching it? When she cast curses, she didn't actually "touch" them with her hands—they simply appeared from her hand, which was the outlet for her magic. Even though it might have looked like Seina used spells through physical contact, like Stupefy, it wasn't really the case. The distance between the spell and the target was just so short it gave that impression. That's why Shikamaru and the others had believed she killed that Sound ninja with a "punch," when that wasn't actually what happened.
"What are you thinking about?" her brother asked, sitting beside her.
"That I'm going to have to run a few tests to avoid hurting myself..."
That was how her training increased from 8 hours to 10, adding 2 extra hours to train her magic. Jiraiya, who had been away on a mission, didn't show up until three days later—having been gone a full week. As soon as he returned, he tested them again on fuinjutsu, surprised by how much they had progressed thanks to the scrolls they had been studying at night.
"I know you're hiding something, you little brats. Just promise me you'll be careful," he said, more serious than ever.
"We promise."
"Good. At this rate, you'll be ready for me to modify your seal in a month," the pervert confessed, to the excitement of Naruto and her.
"Seriously?!"
"Yes," he sighed. "I was hoping we'd have a little more time without training with the Kyu— with Kurama, but I see you're not willing to wait. I'll prepare some fuinjutsu seals in case I need to contain you. I wouldn't want you to lose control and have no way of bringing you back."
"Awesome!"
When February came a few days later, Seina started preparing the genjutsu for Sasuke. She didn't tell Sasuke or Naruto anything to avoid giving away that she would eventually try to awaken Sasuke's Mangekyō Sharingan. To be honest... she didn't know if it would work. Otherwise, wouldn't the Uchiha ancestors have tried something like this instead of resorting to witnessing the death of a loved one?
She also started considering how she might activate the Mangekyō with her legilimency. She didn't know whether to wait until the genjutsu failed, but she wanted to review her memories from when she healed Kakashi, who already had his Mangekyō Sharingan at the time. Actually, it was better to compare both cases now. She got up from her desk and went to find Sasuke.
"Sasuke?" she called from the doorway.
The door opened. Sasuke blinked in surprise, drying his hair with a towel, shirtless.
"What's up?" he asked, letting her in.
She sat on the bed while he dried his hair and searched for a clean shirt.
"Do you remember when I healed Kakashi's eye? I've realized that he already had his Mangekyō Sharingan active back then," she said, catching the towel he threw at her and drying it with a spell. "If I can compare his Sharingan with yours, maybe I'll know how to activate yours."
"Hn. Sounds like a good idea. What do you need?"
"For you to look into my eyes and not resist. Oh, and activate your eyes with 3 tomoe."
Sasuke did as she asked. She looked into those red eyes and fully activated her legilimency. She entered his mind easily since they already shared a bond. She examined the activated Sharingan and realized she was right—there were differences between Sasuke's Sharingan and Kakashi's. But what surprised her most was sensing a curse tied to the Sharingan. Stunned, she didn't attempt to awaken Sasuke's Mangekyō, and he, seeing what she was seeing through their link, began to wonder what the hell that was.
She pulled out of his mind, dumbfounded. It was like digging for gold only to find horse shit. It wasn't what she expected—nor what she wanted.
"What was that?" Sasuke asked, pulling on a shirt, his expression serious. "What was that thing we felt?"
"A curse, but... how?" she asked aloud, blinking without finding an answer. "Does your tablet say anything about this?"
"No, though I have to admit it's a copy. Who knows what the stone tablet says—or if there's info about this at all," he replied, frowning in thought.
"The weird thing is I didn't sense a curse in Kakashi's eye."
Could it have been there, just subtle enough to hide from her? Where did the curse come from? Why was Sasuke's Sharingan cursed? Was his the only one—or were all Uchiha affected by it? And more importantly, what did the curse actually do once it was activated? Sasuke followed her thoughts, also pondering the issue.
"I think we should put the Mangekyō on hold," she said reluctantly. "Right now, the curse is dormant, but not active. We need to find out what it is, who placed it... everything, really. I'll write a letter to Kakashi to see if he knows anything or has noticed anything since activating his Mangekyō."
"And Itachi? We could try contacting him."
"Yeah, him too. Maybe he knows what the stone tablet says and can tell us something. If he bothers to answer, that is..."
So she wrote her weekly letter, including what had just happened. Kakashi, of course, wouldn't reply for weeks. Not until late February, once he returned from his mission, to be exact.
"...I've never heard of anything like that related to the Sharingan, and I can't think of anyone to ask who might know. Honestly, I activated my Mangekyō Sharingan not long after Rin died, which was shortly after Obito. If there was any difference between my normal Sharingan and the Mangekyō, I didn't notice. Then again, I'm not an Uchiha and I don't use the advanced form much. I imagine you've already thought about writing to Itachi. If he ever replies, I'm sure he could tell you something."
Putting aside the new mystery, I still miss you as much as the first day. Maybe more. I thought I'd get used to it, but I can't. I've decided to focus completely on my missions so I don't dwell too much on losing you, and even then, I still can't stop thinking about you. What are you doing to me?"
Seina finished reading the letter with a smile on her face and tears in her eyes that no longer fell. She missed him deeply but knew she would see him again.
February was a strange month. From Jiraiya's promise to find a way to start training with Kurama in March, to her magic training that kept surprising her, and finally, the Sharingan curse that not even the pervert seemed to know existed.
When March came, Jiraiya left on another spy mission.
"You promised to modify our seal, you old perv!"
"I know! And I will!" he raised his hands in a calming gesture. "It's just a minor setback—I'll be back in three days. You'll see."
Those three days became four, then five. On the sixth day, Jiraiya returned and found them all training in their respective areas—Sasuke with Sharingan genjutsu, Naruto working on his rasengan's nature transformation, and Seina with her adamantine chains. Naruto scolded him for half an hour for breaking his promise. Tired, Jiraiya promised to start training the next day—after recovering from the hangover he was currently suffering.
"Who does he think he is?!" Naruto exclaimed as they had dinner alone.
"Clearly, he doesn't take us seriously."
Seina nodded as Sasuke hissed his agreement. Jiraiya was used to doing whatever he wanted during his travels. The last time he had seriously trained anyone—besides the few scattered weeks with Naruto—had been when he trained his father. That was over 15 years ago.
"We should punish him," she finally said. "Every time he breaks a promise, he should get a prank punishment—so next time, he'll think twice."
Sasuke and Naruto grinned mischievously as they caught on to her idea.
"What are you thinking?"
"It has to be something that won't put him or his mission in danger, but still be annoying. Like... shrinking his underwear so it squeezes his parts."
Naruto couldn't hold in his laughter, turning red as he burst into giggles, while Sasuke clearly imagined it, smirking darkly.
"Or maybe enchanting his mirror so every time he looks into it, his reflection insults him."
"Do you remember those fortune cookies he loves to open every week?" Sasuke asked, leaning in. "Could you change the message without him noticing?"
"Of course."
"How about something deep and reflective like: 'Is having sex with your clone incest or masturbation?'"
Seina couldn't help it and burst out laughing, stifling it so she wouldn't wake the pervert. They couldn't hear what he was doing—but he could hear them. Naruto, red again, laughed silently.
"I love that one."
"Just wait till you see his face!" Naruto laughed.