"My name is Shisui Uchiha and I'm here to help you with that little Sharingan of yours."
Harry blinked. Then blinked again while still looking at this Shisui like he had five heads. "Shari-wha?"
"The Sharingan. You know earlier when you were fighting and everything seemed to slow down?"
Harry nodded his head in understanding
"That was the Sharingan at work."
"Does everyone have a Sharingan? Is that why your eyes are red right now? Can it do anything else?" Questions were flying out of Harry's mouth like a machine gun firing bullets
"Woah woah slow down on the questions okay? No not everyone has a Sharingan, it's a family trait. Yes, that's why my eyes are red as I currently have it activated, That's also why that girl you were with was talking about red eyes because your eyes went red when you activated it. Yes, it can do a lot more if you learn how to use it to its full extent."
"Wait a minute, how do you know what me and Hayley were talking about?" Harry pointed a finger at him almost accusingly
"Why because I was listening and watching the whole fight!" Shisui replied joyfully and seemed happy at the fact he had been worked out
...
"YOU WATCHED ME NEARLY DIE AND DID NOTHING ABOUT IT!!!" Harry shouted still pointing that finger
"Woah shut up kid I don't want the nurse coming back"
"I DON'T CARE IT'S YOUR FAULT I'M IN HERE ANYWAY!!"
"Alright calm down for a minute I'll explain okay?" Harry motioned for him to continue "I was watching because I knew you were going to gain the Sharingan and as soon as you did I knew you would win the fight then and there. Never underestimate the power of the Sharingan, I promise you if you ever do that will be your greatest mistake."
"You say that as if there are others with the Sharingan though earlier you said it was a family trait. Does that mean I have more family out there? Also will Adrian and Mum and Dad get it?"
"No and no there are currently no others except me and you with the Sharingan but magic is a strange thing. Also, your family would never be able to unlock it as it seems you are the first person to have it in your family for a long while I do not know who the last was though you could probably find out if you looked into your family history."
"What do you mean magic is a strange thing?"
"I wasn't meant to be here. I had just died in my dimension and I got dragged here to teach you all about the Sharingan. That's why I watched the fight instead of stepping in because I knew you would unlock it and win the fight. After all, I had to eventually teach you about it so you must've lived."
"Also earlier you said it can do a lot more when you learn how to fully use it. Just what exactly can it do?"
"You would be amazed at its full power but that takes a lot of practice and loss"
"Loss?"
"Yes, the Sharingan has forms to it, it goes one tomoe, two tomoe, three tomoe, mangekyou Sharingan and eternal mangekyou Sharingan and to go up through the ranks you have to experience great loss."
"But I unlocked one tomoe without any loss at all?"
"That was because you felt a great fear for your life"
"Oh"
"Look we have been here talking for far too long. How about I take you back to my home and you can rest up there"
"I shouldn't, what about my parents?"
"You nearly died and they did nothing, You're in the hospital for crying out loud and they still can't remember you. So are you going to come with me and master the Sharingan or are you going to sit in your room forgotten about until Hogwarts?"
"I don't know." Harry now looked scared, he had never seen this man before but now he was trying to take Harry back to his house. Talk about stranger danger and all. "I'll go on one condition"
"Name it"
"You swear an oath on magic that you will not try to kill me outside of training and I can leave to go to Hogwarts when I get my letter," Harry thought this was a smart move. He had always wanted to go to Hogwarts ever since he had first heard about it from Dumbledore.
"I, Shisui Uchiha, call upon the divine beings of magic to hear my intent and to swear that I will never try to hurt Harry James Potter outside of training and to allow him to leave when he wishes. So mote be it." Shisui was engulfed in a gold aura for a second confirming the magical oath had taken place "So you ready to go now?"
"Lead the way," Harry said gesturing to the door
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The walk to Shisui's house might've been the longest Harry had ever walked. However, upon arrival, he realised it was worth it. It was a beautiful house, it was big but didn't compare to places like Potter Manor. However, where it was located was beautiful.
It was deep in a forest with trees up to the sky and green vines hanging down however after travelling through this enchanting forest you got to a huge clearing with a huge cliff which had a beautiful waterfall going into an ocean-blue Lake. Upon that same hill sat Shisuis house. It was breathtaking.
Shisui opened the door and the inside was just as beautiful. Everything was oak decor but it still had a modern feel about it. It wasn't too different from Potter Manor.
"Your room is upstairs first one on the right. Settle in and then get to bed early you are gonna wake up at 6 to begin your training, meditate for half an hour then I expect you downstairs at 7:15 for training got it?"
"Yes sir" Harry bowed his head in acknowledgement "What exactly will I be training"
"Well as you know I'm not from this dimension so I can't do magic but I can however do jutsu so we will do jutsu training then hand-to-hand combat and finally Sharingan training"
"What exactly is jutsu?" Harry asked a thoughtful expression on his face
"It's the use of chakra in your body. It's a bit like magic in a way. I will explain properly in our first lesson
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Time Skip 2 Years
The first few days of training were torture. Pure and utter torture Harry struggled with everything. He soon found that he could not do jutsu as it seemed it did not exist in this world. Thankfully that did not affect the Sharingan so any sort of jutsu attached to that he could do fine.
Now with no jutsu training, that time was reinvested into building stamina and Shisui trying to teach Harry magic out of any book he could get his hands on. It worked for a little while until they got to third-year spells where they soon realised that Harry couldn't learn everything from a book.
All in all, however he was making a lot of progress he could now effectively use the Sharingan to the best it could be used with 3 tomoe. He was a very formidable opponent when it came to hand-to-hand. His stamina had come along by a lot being able to run around the forest non-stop for an hour
The worst skill in his arsenal was magic and that wasn't because he was bad at it, he was quite a bit further ahead of everyone. It was just hard learning from books and someone who can't do magic and he felt no progress could be made until he arrived at Hogwarts
All in all, he loved every minute of his time with Shisui and he had done what he had been sent here for, to train Harry with the Sharingan.
Harry was now 10 years old and he couldn't have been any happier with Shisui, he loved him like a father loved his son.
It was perfect for Harry all too good to be true until Shisui sat him down one day.
"Harry you are old enough to know now..." Shisui started a solemn look sketched on his features
"Know what?" Harry's confusion carried into his voice
"As you know I'm from a different dimension where I'm dead."
Harry looked into Shisui's sad eyes "Yeah I know?"
"Well to be truthful with you... I can't stay here forever." Shisui looked into Harry's eyes for the first time since this conversation had started
"Wha" Harry's eyes welled up with tears
"When I was sent here when you were 8 I was only given 3 years to train you." Shisui looked to be on the edge of tears
"How- why" Harry broke down, he didn't care anymore the only man he had ever seen as a father was telling him he was going to die
"When I died in my other dimension I died poisoned and the being I met with told me I could come back here but that poison would eventually catch back up to me" Shisui embraced Harry holding him tight
Harry didn't even bother responding he just carried on crying
"I can feel it, Harry I'm going soon I have a feeling it will be the day we met"
"That's a week away"
"I know, look no training now, you know everything about the Sharingan even the mangekyou and eternal mangekyou Sharingan just me and you time."
"O-ok"
"Listen Harry there's a good chance your Sharingan will evolve into the mangekyou upon my death, I want you to take my eyes and make an eternal mangekyou for yourself."
"I-i can't do that" Harry disgusted by the thought of it
"Harry it's my final wish for it to happen make sure it does, please."
"Okay," Harry said more determined than Shisui had ever seen him
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Harry awoke with tears in his eyes. Today was the day though he wouldn't show he was upset. He wouldn't do that to Shisui on his last day here.
Harry checked around the house finding no sign of Shisui his heart dropped had he already gone and Harry had missed the chance to say bye? No, he couldn't have surely not.
Harry ran into Shisui's room and let out a sigh of relief when he saw him in bed sitting up. However, he did not look good at all
"Harry I think it's time"
"No not already surely not." Harry was crying already! DAMNIT! He was trying to be strong for Shisui
"Harry listen to me your mangekyou will awake take my eyes make it eternal please"
"Yes sir"
"Harry listen to me live your life with no regrets, play pranks, have fun, play Quidditch. Do whatever makes you happy I swear to god if you spend the rest of your life brooding over me I'll come back and haunt you until you die"
"Yes Shisui" Harry let out a chuckle one mixed with pain and humor
"Harry I couldn't be more proud. James and Lily missed out on raising a great boy like you it was an honour from the very start to the very end. I'll love you forever" Shisui started coughing up blood
"Thank you for everything. I don't know what I'd do without you, Dad."
"Goodbye, Son"
The last thing Shisui Uchiha saw was Harry's eyes morph into his mangekyou Sharingan. Shisui Uchiha died with a smile on his face knowing his son was now safe with his new Sharingan.
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Notes
Okay, this really hurts to write this chapter, Sorry it's on the shorter side I'm building up for Hogwart's. Next chapter Harry there!
I'm sorry if it feels like I killed off Shisui too quickly.
Also, I'm really proud of myself rn I've been smashing out these updates recently
Also, do you guys want this to be a Harry x OC or a Harry x multi?
Word count-2032 (including notes)