The hidden Anbu (Naruto Various x Reader)

The Uchiha Brothers

As you all walked back you yawned, stretching softly. Approaching the younger Izuna you where quick to strike up a conversation.
"Hey, uh, would you be willing to train with me? I saw how strong you where on the battlefield and I'd love to be able to match you."
He studied you, narrowing his sharingan at you. He didn't have the Mangekyo yet surprisingly. Staying silent for a few seconds longer he nodded. "I do not see why not. You'll have to keep up."
"Of course." You chuckled. "My name is Atlas, you?"
"That is an odd name Atlas, Izuna is mine."
"Lovely to meet you Izuna." You beamed.
"I will see if my big brother wishes to join us."
"Of course, anything to make you comfortable." You chuckled softly.
"I will be back, with him if he says yes, without, if he says no."
"I understand." You nodded, continuing to walk as Izuna walked over to a long haired Uchiha, walking back with him.
"Brother, this is Atlas, Atlas this is my brother Madara."
Madara raised an eyebrow at you, shaking his head. "She'll be easy to beat. Why do you need me brother?"
"Just watch over us big brother?" Izuna smiled shyly, "I'd feel better for the first few training sessions if you did so."
"Anything for you brother." Madara chuckled, patting Izuna's head softly. Beaming at the relationship between the two you walked beside Madara, who had placed himself between you and Izuna.

The next day you met up with Izuna and Madara, shaking with slight excitement.
"Ready Atlas?" Izuna smirked. "I have my third tomoe so you can't beat me."
"Oh? I can't beat you?" You chuckled. "Well, we will see won't we?"
"Do you even have yours?" At that questioned you beamed.
"Yep! And you can't beat it." You smirked at him.
"We'll see won't we." Izuna and you bowed to each other, before the spar started. Izuna starting out with activating his sharingan. You kept yours put away, seeing as you needed a few seconds so you didn't show your Sheshigan to them.
Rushing forward you kept your eyes away from his, unluckily for him you had been sparring the ghost him every chance you had, to learn ancient fire jutsus. Lucky for him, it was hard to do anything against him without pulling out your yin or yang jutsus because the techniques you had were fire only.
"Outlandish Eruption!" You called out, an eruption of fire from the ground covering his sight as you activated your Sharingan, you only had the mangekyou sharingan though. Luckily without any of the side effects since you got Shisui's and his is now a pseudo Eternal.
Izuna was quick to dodge everything, grunting with effort as fire surrounded him and erupted out from under him.
Rushing forward his blade met your borrowed blade. The Uchiha made Tanto felt weird in your grasp to your Delone made blades, but it would do.
"Secret Salamander Jutsu!" Hundreds of tiny fire salamanders rushed towards him, crawling up him as he rushed to get them off. Rushing forward you smirked, pushing against his blade. "Think you can still win?"
"You think you'll win?" He finally looked up, eyes widening. "...Mangekyou..."
"Yep. Keep trying though!" You jumped back as you put out the Salamanders.
"Stop!" Madara had finally had enough. "Enough. Talk out strategies, and how to beat different jutsus."
Keeping the sharingan active you placed the borrowed Tanto into a sealing scroll. "Good job,"
"What were those jutsus!? I've never seen anything like that!"
"I'll teach you." You smiled. "Swear on my dad."
"Nice! We're really lucky to have you."
"We'll i'll do my best." You bowed slightly.
"How did you get your mangekyou? Our father won't tell us how to unlock it."
"I woke up with it, honest, I don't remember how I did it."
Izuna narrowed his eyes but nodded. Clearly he didn't believe you, but it was how you got it mostly.
"Why haven't you fought on the battlefield before?"
"Because, I wasn't allowed too." You smiled sadly, "I wanted to help but I wasn't allowed."
"Well, from now on you need to be on the field."
"I agree." You nodded as you spoke. "Now which one do you want to learn? All of them are based on the amount of chakra you put in. Which works great for me because I don't have a whole lot at my disposal despite having a large reserve."
"Hmm..." Izuna looked to be thinking, "The Salamander, they where hot."
"Right okay, so I'll form one Salamander, and make it barely hot enough to hold." Doing so you beamed, holding out the Salamander. "It's not a summon, it's pure chakra like a water dragon."
Izuna nodded, listening as you explained.
"The handsigns are Bird, Dragon, Monkey, Rat, Ushi, Mi, Tiger. Start slow because you can accidently add too much chakra at first and overwhelm the area."
Seeing him nod and slowly do the hand signs, you watched along. "Slow the rate of your chakra, I can feel it burning quickly."
"What are you a sensor?" He laughed.
"No, just close enough to tell." You chuckled, not mentioning that it was the fact that you had felt his ghostly chakra often enough to know what it was doing.
"Secret Salamander Jutsu!" He called out forming around a dozen Salamanders, who each rushed off into a different direction.
"Wait wait cancel the jutsu!"
"How?!" He panicked slightly as a tree lit up.
"Stop your chakra flow! Halt it!"
He did so, breathing in relief as the fire went out, and the salamanders disappeared.
"The other one?" He laughed in slight nervousness.
"Outlandish Eruption? Ah yeah, I sorta did tear up the terrain with it. It's not the best for a small scale battle." You laughed weakly, "But it is fucking cool huh?"
"Yeah." He nodded, "Where did you learn it?"
"From a friend, he... he's not here anymore."
"Oh, I'm sorry."
"It's okay, it's not your fault." He nodded at your words.
"But I'll teach it to you Izuna."
"Thank you Atlas, I'll make you proud." His smile radiated warmth.
This is the day, that you knew, you'd never be able to leave these two without grieving for them and their lost lives, for you knew their fate and how their story would end.