Five years passed... During that time a lot of things happened, Kaen as usual, only focused on his training like a madman. he managed to sense natural energy in the surroundings due to his inherited sage body.

He found a way to masked his chakra from perception ninjas during his infiltrating mission as an Anbu.

It was achieved by using the natural energy as a protective cover on his charka, thereby making it invisible to other ninjas.

But, he still decided to stop himself from using natural energy to nourish his body lest he turns into stone for absorbing too much.

but that's not all of it, his true discovery was he managed to create a nigh-absolute self-created healing technique.

The principle is by combining his monstrous regeneration and his special body's trait which was immune to poisons and diseases, he managed to combine them and create a technique that can heal even internal organs, limbs, diseases, and poisons.

But, its limitation is it can't revive a dead person yet and he was the only one who can use it, furthermore, the biggest drawback was, the severe the problem the bigger amount of consumption. it was exhausting to lifeforce as well, Fortunately, he has Uzumaki blood.

just reaching a whopping 50% of his current chakra, even with his current chakra capacity he can only use it to heal grave injuries two times.

Izumo Tenma dies by Uchiha Obito's hand; Uchiha Itachi awakes the Sharingan...

Kumo ninja tries and fails to kidnap Hyuga Hinata; Hizashi Hyuga is killed in his brother's place as a result of the incident...

Team Ebisu is born (Sarutobi Konohamaru, Kazamatsuri Moegi, and Udon); Uchiha Itachi becomes a Chunin...

Inari is born...

Umino Iruka becomes a Chunin; Hyuga Hanabi is born...

Uchiha Itachi joins the ANBU; Uchiha Izumi graduates from the academy; Konoha implements a minimum graduation age of 11...

Kaen was promoted as a squad leader and Itachi joined his team...

Kaen and Itachi didn't talk that much, but Itachi's respect for him was apparent, they did a lot of missions together and they had their own tacit understanding.

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[Kaens' Shitty House]

In a shabby bed, a man was sleeping, loud snoring can be heard. In one of the gaps of the roof, warm sunlight entered signifying that resting time has ended.

Kaen's eyelid suddenly twitched due to the light being directly under his face.

"The sunlight was truly annoying at times"

He got up to his bed and put on his loose t-shirt, he decided to wash his face to wake the shit out of him thoroughly.

"Hmmm... Today will be the time that Shisui died in the manga"

Kaen was preparing methods to save him while not interrupting Itachi Uchiha's awakening of Mangekyou Sharingan.

Thus, Kaen decided to follow Shisui using his anti-chakra surveillance, and decided to intervene when the right time comes.

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Just like that, the plot proceeded.

Shisui addressed Hiruzen Sarutobi, telling the truth to the Third Hokage, as the Uchiha grew angrier and more violent due to the village's suspicions of their role in the Nine-Tailed Demon Fox's Attack. Hiruzen trusted Shisui since he is a descendent of Kagami Uchiha, and he permitted the Uchiha to spy on his clan for the village.

Shisui was confused that the clan would not back down from their planned coup d'état, and he became increasingly anxious about the ramifications of their actions. Shisui was eventually persuaded to use his Kotoamatsukami on Fugaku Uchiha in order to put an end to the coup d'état plot.

Danzo Shimura, fearing that simply influencing the Uchiha's leader would not solve the battle and that he would eventually try to control him as well, elected to take Shisui's eyes for himself in order to safeguard the village in his own manner as Shisui prepared to make his move. As Danzō and his men surrounded Shisui to take the left eye, Shisui managed to escape.

This tale has been pilfered from Royal Road. If found on Amazon, kindly file a report.

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[Near the cliff, Naka River]

Shisui gouged his left eyes out under the terror-stricken face of Itachi, He let out a smile even with the tremendous pain he was currently experiencing. "Brother I will entrust you my eyes, don't let it fall on Danzo's hands."

"Brother Shisui, don't! there are other solutions! we can find another way..."

Itachi Uchiha was trying to convince his brother, he was thoroughly desperate.

"You don't understand" Shisui walk near to Itachi and clasped his hand to let Itachi hold his remaining left eye, "The situation was more complicated than I originally assumed."

"You will understand it soon, please protect the village and our family name"

After saying his last words, he jumped on the cliff.

"Ahhh!!!" Uchiha Itachi shouted in despair, he slumped slightly on the ground, due to his current emotional state, he didn't manage to witness a shadow that suddenly crept across the cliff where Shisui jumped.

After regaining his bearing, Itachi looked at the sky his face was blank and full of indifference.

His eyes had completely changed, it finally transformed to Mangekyou Sharingan, "So this is the requirement necessary to obtain these eyes".

He walks to the forest and stared at the place one last time, "Brother don't worry I will take care of it, rest in peace."

His face that was full of indifference was replaced by determination, he clenched his fist one last time before vanishing.

Kaen watched the whole drama unfolded before his eyes, besides him lay the unconscious Shisui, the previous empty eye sockets were nowhere to be seen.

It was replaced by violet irises that were rotating continuously.

"Unbelievable, his eyes mutated to Rinnegan?'

Kaen placed his hands on his chin, 'Hmmm... did this happen after I healed his gouged eyes?

'Should I gouged my eyes too?'

Kaen quickly shooked his head at the absurd idea.

'No, I decided to obtain strength to protect myself, not to harm myself just to obtain power.'

Even he, can't explain the current bullshit happening, he was speechless at the current situation.

he quickly took out his syringe, and get Shisui's blood while he was unconscious.

'I feel like I was being used to this kind of feeling, Would I become the strongest thief? No... no... I was doing it as compensation for healing him, yes that's it!

Kaen convinced himself quickly and carried Shisui to the side, deciding to wait for him to wake up before proceeding to his plans.

After three hours of waiting... Uchiha Shisui has finally woken up.

He managed to stand, his face was confused... he remembers that he jumped on the cliff after that before losing his consciousness, he managed to sense a shadow heading on his place.

after thinking about it, Shisui's thoughts trailed and quickly scanned the surroundings as if finding an answer. Then it suddenly occurred to him why could he see? how did his eyes return? he was truly confused but decided to focus on things first.

And then, just like that...

he didn't find anyone...

Just as he was about to find something to eat to calm his raging stomach, he was startled by a voice that suddenly appeared behind him

"Yo!" Kaen was standing behind Shisui with his usual easy-going smile. "It seems that you're finally awake."

Shisui looked at the man who suddenly appeared out of nowhere, even with his excellent perception he didn't manage to even sense him, he quickly decided not to underestimate him and looked at Kaen vigilantly "Who are you?"

Kaen was amused by his reaction, he ruffled his hair slightly, he spoke.

"Was that how you treat your savior?

Uchiha Shisui was astounded, but after being reminded of the weird situation and black shadow he quickly manages to connect the dots. " I apologize for my rude behavior, I am Uchiha Shisui of Konoha, may I know you're name sir?"

"I am... Well my name is Senju Kaen, Kaen was just fine"

He chuckled at the thought, he stared at Shisui with a friendly smile and offered his hands.

Uchiha Shisui who was friendly by nature quickly took it, he was not surprised about him being Senju in the slightest, because, for a person who saves him, not to mention having this kind of strength, he has his own way to determine a person's nature just by looking at them. "So you are the one causing waves in the Anbu team, Dark joker right?"

'As expected of the strongest genjutsu user in Konoha, he was truly bright'

Kaen just shrugged, "Well, I know you have some questions, so just ask I will answer it as clear as I can."

"Thanks" He looked at him with a bright smile.

Kaen then explained to him the events that happened, like how Itachi opened his Mangekyou Sharingan after he jumps, he also explained to him his plans.

"Dealing with Danzo huh..." Uchiha Shisui became silent for a moment, being reminded of the one who almost caused his death, he can't help but felt a bitter taste in his mouth.

"Sounds good to me"

Uchiha Shisui grinned, even though he was not the petty type of person, but he also wants to vent on Danzo for what happened.

Kaen who heard him say it, smiled slightly, he has finally a competent ally who will help him achieve his goals, Shisui agreed to help him help on his conquest, he asked "Are you sure don't want to stop Itachi from massacring your... clan?"

Hearing his question, Shisui just smiled bitterly, he looked at the distant sky with a solemn expression, "Our clan needs to be renewed from the roots, for that to happen this massacre is needed, the clan members became arrogant and regarded themselves highly"

"This needs to be removed, then the future generation will remember this lesson and not walk the same path as their predecessors."

Kaen looked at Shisui's serious face, he nodded and said "Fair Enough, so that means you need to hide for quite a long time"

"It doesn't matter" He looked at him with a teasing smile, "Time is the last thing we need to worry about"

"Well, yeah, so are you ready? let's beat the Danzo!"

Uchiha Shisui chuckled at his antics and take a look at his leaving back, he quickly followed him and shouted, "Hey wait for me, can't we eat something first?"

Kaen who was running ahead stop momentarily and looked at him speechlessly.

"Well, we still have some spare time, do what you want."

Shisui quickly disappeared in the opposite direction to hide his embarrassment, and hunt some animals to cook.

Kaen was scratching his cheek at the sight, "So this is the famous Uchiha Shisui."

'Well, scratch it, we all have our own embarrassing moments"