Though Yuu had been in the Naruto world for over half a year, the system had only awakened three months prior.
He’d been overjoyed the moment it activated.
That very first day, the thought of Obito eventually turning on and slaughtering the Uchiha clan — and possibly him too — had made him starve his brother and jot it down in his journal.
That was when the system spoke:
> [Detected: Obito falls asleep seething with deep resentment toward you.
Extract Yin chakra from target?]
At first Yuu had no idea how valuable that reward was — until he recorded Elder Uchiha Sora using the Sharingan for mental training, and the system revealed the secret behind awakening the eye:
Yin chakra is the very foundation of the Sharingan.
In that moment, Yuu understood: the “special chakra” said to surge through the brain in response to trauma was nothing more than highly concentrated Yin chakra.
Knowing the truth was one thing; generating it was another.
Chakra is formed by blending physical and spiritual energy in precise measure — isolating and cultivating pure Yin or Yang chakra is nearly impossible.
Only the Uchiha bloodline grants even the slightest edge in drawing forth Yin chakra, and you need a substantial amount of it to awaken the Sharingan.
As for the need for intense negative emotion?
That’s just one way to produce more Yin chakra — not a strict requirement.
Negative feelings raise the odds of awakening because they make it easier to generate that energy, but they aren’t mandatory.
Obito’s natural ease in cultivating Yin chakra was exactly what made him so valuable to Madara.
If Obito’s reserves were thinner, Madara never would have set his sights on him — and that was why Yuu truly believed he was doing this for his brother’s own good.
Awakening his own Sharingan was Yuu’s top priority.
Perhaps because he was a reincarnated soul, his spirit still clung to his old world’s mindset — making it incredibly hard for him to produce Yin chakra on his own.
On top of that, prices were skyrocketing as the Third Shinobi World War loomed.
To get by, he took missions, and used his knowledge of the future to team up with members of Konoha’s noble clans.
After all — three Uchiha working together would look far too suspicious to Danzō.
Opening his system journal, Yuu saw every entry marked with a bright red exclamation point, waiting to be claimed.
He skipped past the first fourteen, and selected the one about Obito.
Pure Yin chakra flooded into his body.
It felt cold, heavy — like something unclean seeping into his veins — and instinctively pulled toward his eyes, as if drawn by something hidden within them.
When he opened them, a sharp pain shot through his vision.
He squeezed his eyes shut fast; he’d never felt anything like this before.
Did something go wrong?
He’d used up all fifteen entries for the day.
He’d have to wait until midnight to log another note and see what the system said.
After a while, he opened his eyes again — everything felt normal.
He let out a breath he hadn’t realized he’d been holding.
He did notice, though, that he’d been slipping into darker thoughts more often lately.
But that was easy enough to fix — all he had to do was tease Obito a little.
It hurt his brother, sure… but it hurt him too.
And if his theory held true: strip Obito of the trait Madara craved, and he’d change his brother’s fate entirely.
“Someday you’ll understand, Obito,” Yuu said with quiet confidence.
“Now — what else did I get?”
He scrolled through the rest of his entries:
> [Record: Ordered a large bowl of Ichiraku Ramen.
Feedback: The owner skimped on the beef — he thinks you’re an Uchiha who can afford it.]
“Knew the portion felt off.
Even Ichiraku’s bought into the bias, huh?”
> [Record: Turned in mission, claimed reward.
Feedback: The clerk passed your mission log straight to ROOT.]
“So that’s how they first noticed me.” Yuu nodded, though something still felt off.
The rest were trivial details he skimmed right over.
Then he pulled up the entry about the Third Hokage’s graduation speech:
> [Feedback: Hiruzen Sarutobi’s thoughts: This Uchiha boy, Obito… he is nothing like the rest of his clan.
He fits the Second Hokage’s screening criteria.]
“The Second?
Tobirama Senju?
He’s dead!
And what screening criteria?”
Obito really was a walking target — Madara wasn’t the only one with plans for him.
The hint was far too vague, but if he kept logging every interaction between the Third and Obito, he might unravel the secret eventually.
> [Record: Being watched by ROOT… Feedback: You’ve sensed their presence.
Your five senses sharpen slightly — chakra cultivation speed improves, and danger intuition grows stronger.]
A prickle ran down his spine.
That must be it.
He’d felt it before: during his very first B-rank mission, a gut instinct had let him dodge a killing blow before he even saw it coming.
“Last one — logged Inuzuka’s drunk antics.
Hope it boosts my sense of smell again… though he really went overboard today.
And Aburame was drinking too?
Didn’t he say alcohol messes with his bugs?”
He smiled, thinking of the two friends he’d made over the last six months.
> [Record: Inuzuka’s drunken embarrassment… Feedback: Inuzuka Kiba’s thoughts: ROOT agents warned me and Aburame not to get too close to Uchiha Yuu — especially not on missions.]
“Afraid an Uchiha is getting too friendly with the other clans?
Following Tobirama’s old isolation policy, then?”
A chill ran down Yuu’s spine.
That intuition had saved his life more than once — and it screamed that something was very wrong.
ROOT wasn’t just watching.
They were planning to eliminate him to keep him from gaining influence elsewhere.
He’d been so careful… yet they still wouldn’t let up.
A dark surge of anger flared in his chest — and his eyes stung again.
He grabbed a mirror and stared.
He’d awakened the Sharingan.
Just like that?
He’d heard only one in ten Uchiha ever unlocked it — but then again, Obito had gone straight to the Two-Tomoe, and later all the way to the Mangekyō.
It must have been the mix of Obito’s Yin chakra and his own sharp spike of anger.
It felt far too easy — like he’d done nothing at all to earn it.
“…I did work for it!
Negative emotion matters too!
And besides — being the older brother of the future ‘greatest villain’ has to count for something, right?”
He’d found his excuse.
But there was no time to relax.
As long as he’d kept his eyes closed, he’d stayed off ROOT’s radar.
Now that he’d awakened the Sharingan, he’d be at the very top of their list.
And his gut told him they were already coming for him.
ROOT Headquarters
The same two agents who’d warned Kiba and Aburame were now picking a mission to send Yuu to his death.
If he took the bait, they’d have all the excuse they needed — and Danzō had given them full authority to do what was necessary.
They intended to make this permanent.
They knew nothing of Tobirama’s screening plan — only that Danzō held Obito in high regard, and had strictly forbidden harming him.
He also wanted no distractions around the boy.
That was why You was marked for elimination.
Watching Obito, they’d seen how his brother never seemed to care for him — even starved him for no reason.
Someone who mistreated the clan’s most promising asset didn’t deserve to live.
Surely Obito felt the same way — hadn’t he cried out “Are we really brothers?”?
They were just doing him a favor.