That evening...
Naruto and Yūgao headed to the hospital, a box of pastries in hand.
Gekkō Hayate, lying in his bed, was receiving the best care.
As an elite ninja, his wounds were being treated well.
— "Hayate-nii, please get better soon..."
Naruto handed him the pastries.
A rare gift, prepared by Mikoto herself.
The reason for such a present?
Borrowing his beloved... just for tonight.
— Cough... "Don't worry, I've still got at least ten years left in me..."
Hayate smiled, touched.
His pale complexion and dark circles betrayed the side effects of the Touton.
If I master 'Yang Release applied to others'...
I could heal Hinata's mother... and Hayate too.
Yūgao... Your sacrifice will save lives.
Only Kyūbi could see the darkness behind those thoughts.
Unaware of it all, Yūgao and Hayate saw only a kind and caring boy in Naruto.
After a few exchanges, Yūgao was preparing to leave.
— "Get some rest, Hayate..."
— "Don't worry, the medical staff is taking good care of me."
As she closed the door, Yūgao kept her lover's smile in mind.
...
It was 8:30 PM when they left the hospital.
Night had fallen.
Naruto would head home, while Yūgao would discreetly watch over him.
On the surface, she had nowhere to stay.
But in truth, the council had assigned her a room right across from Naruto's.
A window facing directly into his...
And since Naruto never closed his curtains...
Everything was visible.
As she was settling in for what seemed like an ordinary night, Naruto surprised her.
— "Uh... Yūgao-neechan... I'm having a problem with my training. Could you help me?"
He scratched his head, looking embarrassed.
— "Of course!"
Her answer was immediate, almost too eager.
Finally... I'll be useful to him.
— "Awesome~!"
Behind his smile, mischief was brewing.
...
Click.
The light flooded the room.
Yūgao noticed the house was cleaner than last time.
Did Aoba from the Hyūga clean up?
Back at the academy, they had been mere classmates.
— "Yūgao-neechan, here's some tea."
Naruto returned from the kitchen, cup in hand.
— "Thank you..."
She removed her mask, revealing her porcelain face.
Sitting across from him, she listened as he explained his issue.
— "I'm stuck on the 'Yang Release'..."
The Yang Release?
Yūgao remembered the orphanage.
His Yang chakra was so strong that day...
But she wasn't an expert in the field.
Still... Even Nonō wouldn't be able to help him.
— "I'm trying to fuse 'Yang Release' with Kyūbi's chakra..."
Naruto detailed his research.
A novel approach since Konoha's founding.
No one has ever tried to tame a Bijū like him.
Controlling three tails while remaining sane was already a feat.
Meanwhile, Naruto was analyzing Yūgao's every reaction.
The Yang Release affected the body.
Tested on myself: no problem.
Kyūbi's chakra amplified all abilities.
But combining them?
No one's ever tried.
And more importantly...
What would happen if that fusion was used on someone else?
Previous attempts had shown that Yūgao couldn't handle Kyūbi's chakra.
Skin contact: slowed healing.
Mental contact: confusion, brief amnesia.
And with the Yang Release added...?
Naruto burned with anticipation.
— "So... Yūgao-neechan, would you help me test it?"
He phrased it carefully.
Not a word about being a guinea pig.
Just a friendly sparring session.
— "Alright."
Yūgao set down her cup.
It'll be fine.
Even if he beat Zabuza... He wouldn't hurt me.
She stood, determined to be useful.
— "I'm starting, Yūgao-neechan..."
Naruto took position.
— "Kid, are you sure?" growled Kyūbi.
Even I don't know what's going to happen.
To impose our power on such a fragile human...
— "It's fine."
Naruto smiled inwardly.
No matter what...
She won't escape me.
BOOM!
A crimson chakra cloaked his hand.
Then, tinged with Yang, it turned black, then violet.
An energy reminiscent of Menma from the movies...
This dark power was the fruit of his post-mountain experiments.
A new force for me.
But for kunoichi like Yūgao...?
— "What is that...?!"
Yūgao's eyes widened, alarmed by instinct.
Too late.
Naruto lunged.
THWACK!
She blocked with her forearm, but the contact instantly paralyzed her.
Thanks to the metal plate... Otherwise, worse.
Then Naruto leaped again, his shadowy hand closing in on her face...