The problem was that Shu’s Cursed Energy Manipulation was still far too crude.
Most of his Cursed Energy had been wasted through uneven output and imprecise control.
‘If I can raise my maximum Cursed Energy Output and control every bit of it precisely, injecting every last drop into my optic nerves…’ ‘Maybe I can strike while the iron is hot and break through again, straight to Three-Tomoe.’ But how could he forcibly improve both his output and precision in such a short time?
“Heh…” Shu’s lips curled upward.
“All right.
Time to show some real technique!” “Let’s take out a loan and see just how far this system can be pushed!” “I, Uchiha Shu, permanently relinquish my own Innate Technique in exchange for an absolute increase in my talent for Cursed Energy Manipulation and Cursed Energy Output!” That’s right!
This was one of the most broken mechanics in the Jujutsu Kaisen power system— Binding Vows!
In that world, anyone possessing Cursed Energy—whether a Sorcerer, Curse User, or Cursed Spirit—could impose a special Binding Vow upon themselves.
By deliberately restricting one ability or paying some form of price, they could receive an enhancement in another area.
The most classic example was Revealing One’s Hand.
During battle, a Sorcerer could deliberately reveal information about their Cursed Technique and its weaknesses to the enemy.
By accepting that disadvantage as the price of a Binding Vow, the technique’s power would increase afterward.
Admittedly, the concept became pretty hilarious later in the original story.
Ryomen Sukuna, the so-called King of Curses, became especially infamous for using countless Binding Vows whose costs looked trivial or downright ridiculous to everyone else.
Yet those vows repeatedly granted him enormous tactical advantages and helped him turn losing battles around.
It made countless readers complain that the balance behind Binding Vows was completely broken.
And honestly?
It kind of was.
But even that broken system had limits.
You obviously couldn’t make some idiotic vow like, ‘I’ll eat one fewer bun for breakfast tomorrow in exchange for my next punch landing a Black Flash that blows Six Paths Madara’s head off.’ A vow like that could never work.
At its core, a Binding Vow usually followed a simple principle.
Pay the price first.
Receive compensation afterward.
Once the vow was established, the process couldn’t simply be reversed.
If you later violated a vow imposed upon yourself, the enhancement would not only disappear, but you could also suffer severe backlash.
Binding Vows with a limited duration could technically be broken.
Permanent Binding Vows, however, were different.
Once established, they lasted for life.
In other words, a Binding Vow was essentially a lower-grade form of equivalent exchange.
The more you sacrificed, the more you could receive in return.
Of course, it couldn’t truly compare to alchemical equivalent exchange.
Almost anything could be offered as the price of a Binding Vow.
A limb.
A permanent portion of your power.
An oath never to perform a certain action again.
Even your own life or soul.
All of those could serve as significant prices.
But that didn’t mean you could exchange them for absolutely anything you wanted.
The upper limit of a Binding Vow was that it could enhance some ability or attribute you already possessed.
Cursed Energy Output.
Technique precision.
Attack range.
Things like that.
It couldn’t spontaneously increase your total Cursed Energy reserves.
It couldn’t create matter from nothing.
And it absolutely couldn’t make you perform something you had no ability to do in the first place.
But forcibly increasing control precision and output?
That was exactly what Binding Vows excelled at!
The moment Shu completed the oath in his heart— Bzzzt…!
He clearly felt some invisible shackle descend upon his soul.
From this moment onward, he had permanently lost any possibility of using his own Innate Technique.
Admittedly…
He didn’t even know what his Innate Technique was yet, since the Main God sold every ability separately!
But in exchange—His perception, control, and output of Cursed Energy underwent a complete transformation.
Before, drawing out his Cursed Energy had felt like forcing water through a narrow stream.
Now that channel had suddenly expanded into a vast river.
Shu could even precisely control the flow and shape of every strand of Cursed Energy.
“As expected of cultivation through debt!” Shu was extremely satisfied with how naturally the Cursed Energy now obeyed him.
Trading away an unknown Innate Technique for the extreme control and output he desperately needed right now was an absurdly good deal.
Besides, it wasn’t like he’d become completely incompatible with Cursed Techniques forever.
This was the Main God Space.
His Binding Vow only sacrificed his own Innate Technique.
So couldn’t he just spend money later and buy someone else’s technique from the Main God?
In a place where even divine bloodlines could be purchased, ordinary Cursed Techniques were nothing special.
As long as he had enough Side Plots and Reward Points, he could buy Limitless or even the Ten Shadows Technique.
“Exploiting loopholes in the rules really is a Reincarnator’s traditional virtue.” Shu suppressed his grin.
There was no point thinking about those distant possibilities yet.
He calmed his breathing and adjusted his Cursed Energy to its optimal state.
Everything was ready.
Just like before, Shu guided the Cursed Energy toward the key nodes of his optic nerves.
But this time, his radically improved control made all the difference.
Not a single strand leaked away.
Every bit of Cursed Energy was injected directly into his Sharingan!
Bzzzt…!
Shu squeezed out every last trace of Cursed Energy and poured it into both eyes.
Within his crimson vision, the Two-Tomoe Sharingan began resonating at an incredibly high frequency.
A surge of chakra rippled outward.
Then, beside the two existing tomoe, a third pitch-black tomoe slowly emerged.
Three-Tomoe Sharingan—Awakened!
Three tomoe formed a complete ring around each pupil, rotating at a steady speed.
Shu slowly rose and looked around.
With the Three-Tomoe Sharingan active, his dynamic vision, microscopic perception, and sensitivity to energy flow had all undergone a massive leap.
Even tiny specks of dust drifting through the air became perfectly visible.
He could distinguish the slightest angles at which light from the Main God’s sphere refracted across the plaza.
It almost felt as if everything around him had slowed down.
“Success…” Shu touched the corner of his eye and quietly savored the power flowing through his vision.
What pleased him most was that evolving his Sharingan this way hadn’t affected his mental state at all.
He didn’t have to follow the usual Uchiha path.
The stronger their eyes became, the more emotionally extreme they seemed to grow, until they eventually turned into lunatics screaming about creating a world where Rin existed.
Shu had spent only 1 C-Rank Side Plot and somehow leveraged it into a Three-Tomoe Sharingan worth a B-Rank Side Plot.
And on top of that, he’d practically gotten a Grade 3 Sorcerer’s Cursed Energy system for free!
‘Just as I thought!’ The true essence of the Main God Space wasn’t blindly upgrading a single power system step by step.
It was combining abilities from countless worlds until they started reinforcing one another.