Seeing that Tsunade wasn't joking, Tanaka no longer hesitated and directly activated his Byakugan.
Following her instructions, he carefully controlled the intensity of his ocular power. He didn't look through her entire body—only through her clothing.
"Hm?"
In his Byakugan's vision, her clothes had indeed disappeared, but two private areas were each covered by objects resembling nipple covers and a thong.
Seeing this, Tanaka felt a strange sensation.
Is it just an illusion, or do these clothes seem like they're part of the body itself?
"After looking at them for a while, do you even start to feel like these two parts of the body naturally have nipple covers and a thong?"
"These are actually clothes made from a special material similar to chakra metal. In the shinobi world, especially in Konoha, every kunoichi basically owns at least one set."
Seeing Tanaka's expression, Tsunade was certain—he had never used his Byakugan to see through a woman's clothing before. At the very least, he had never done it to a kunoichi. This realization made her impression of him rise significantly.
"Wearing clothes made from this material still allows your Byakugan to see through the body—seeing the chakra pathway, pressure points, and chakra flow. But in the Byakugan's vision, the body parts covered by this material appear as if they've fused with it."
"This is also the fundamental reason why your Hyūga clan wasn't wiped out by my grandfather and great-uncle back in the day."
Hearing this, Tanaka couldn't help but break out in a cold sweat, feeling a deep sense of relief.
Thankfully, the shinobi world had this chakra-infused material for underwear. Otherwise, his chance to be born into this life might have been erased by Hashirama and Tobirama.
"Alright, move your eyes away from there and focus on the chakra."
Tsunade pointed at Tanaka's Byakugan, then gestured toward her chest before raising her fist.
"This is..."
Tanaka widened his Byakugan.
In his vision, her chakra flowed along her chakra pathway, gathering in her fist.
Then—
Bang!
She threw a punch downward. A violent force accompanied her fist, striking the training ground.
Boom!
With a thunderous explosion, resembling a cannon blast, cracks spread out from the point of impact, covering most of the training ground.
From a distance, it looked as if the earth itself had flipped over.
The power of this punch was easily on par with an A-rank jutsu.
No wonder Tsunade rarely used medical ninjutsu, genjutsu, or other techniques in battle. She simply relied on her chakra enhanced strength and devastating kicks.
A single punch had the force of an A-rank jutsu.
Who needed jutsu when you could just punch?
She didn't even need to bother with hand seals.
"I see... So this is chakra enhanced strength."
Tanaka's gaze sharpened.
Since Tsunade had deliberately slowed down each movement, he could clearly observe every detail.
At the moment her fist struck the ground, the chakra condensed in her hand was released, detonating like an explosive shell and creating a ground-shattering effect.
"If I remember correctly, you once said you were interested in Strong Fist techniques."
"Apart from the Eight Gates, the pinnacle of Strong Fist techniques is the Senju clan's chakra enhanced strength. If you master this and combine it with Gentle Fist, now that would be interesting."
After painting a grand vision of merging chakra enhanced strength with Gentle Fist, Tsunade waved her hand at Tanaka and walked away without looking back.
As one of the Sannin, she had her own matters to attend to.
Even if she wasn't managing the medical ninja training system, her daily training was essential.
After all, this version of Tsunade was not the disheartened, blood-phobic one from the original timeline.
More importantly, during today's meeting at the Hokage Building, Tanaka's words had ignited her obsession with the Yin Seal.
"Chakra enhanced strength combined with Gentle Fist..." Tanaka murmured, his eyes flickering.
With his Byakugan, he had fully analyzed the mechanics of Tsunade's chakra enhanced strength. This made him realize—her decision to teach him wasn't made on a whim but was a carefully considered choice.
After all, she didn't have the Byakugan—she couldn't see through things, nor did she practice Gentle Fist.
So before concluding that Gentle Fist and chakra enhanced strength could complement each other, even someone like Tsunade, a master of both medical ninjutsu and taijutsu, must have spent considerable time thinking it through, perhaps even testing the idea.
That was why, while teaching him chakra enhanced strength, she also pointed out how it could be combined with Gentle Fist.
Like a true mentor, she had paved the path for his future in taijutsu.
"Looks like I have another taijutsu style to learn."
Tanaka thought to himself.
Taijutsu or rather swordsmanship combined with Haki and Devil Fruit abilities.
Chakra enhanced strength and Gentle Fist, combined with Haki and Devil Fruit abilities.
These were the two paths he had chosen to follow.
They were also, in his mind, the best way to integrate the power systems of Naruto and One Piece into a cohesive fighting style.
On top of that, he planned to use the Eight Gates and Haki as his trump card.
If he could master these combinations, he believed he would possess the power to stand at the pinnacle of both worlds.
After obtaining Tsunade's training method for chakra enhanced strength and planning his growth path, he threw himself into intense training.
Mornings were spent molding chakra, and practicing the Op-Op Fruit's abilities as well as chakra control. Afternoons were dedicated to taijutsu and swordsmanship. In between, he indulged in four large meals made from Sea King meat.
Day after day, he remained within the Hyūga compound, paying no attention to the uproar he had caused in Konoha after instantly defeating the ANBU commander.
For 20 straight days, he lived a simple four-point routine:
Train, eat, sleep, spar with Hyūga jonin.
A complete shut-in.
For most ninjas, 20 days of training wouldn't yield significant results. This was especially true at the age of eight, when the body hadn't yet entered its prime development phase.
But Tanaka was different.
For him, 20 days was enough to bring about a qualitative transformation.
His progress in the chakra system alone could only be described as advancing at an astonishing pace.
With the foundation of the Hyūga clan, Tsunade's daily guidance, and the nourishment of Sea King meat, his chakra reserves, taijutsu, swordsmanship, and ninjutsu had all undergone breakthrough improvements compared to when he took the jonin exam.
As for genjutsu, he hadn't focused much on training it, but he had put significant effort into breaking through it.
Moreover, due to his intensive training, high-energy diet, and growing mental strength, his power had been increasing daily.
With the Byakugan, while he couldn't see through and reflect genjutsu like the Sharingan, he could at least see through illusions.
After all, even Ao, who only had a transplanted Byakugan, was able to see through the genjutsu cast by Danzō using a Mangekyō Sharingan, which belonged to none other than Shisui.
Let alone Tanaka, an authentic member of the Hyūga clan.
"It's time to set off for the One Piece world."
Tanaka made his final preparations.
Today was the day he was scheduled to meet Rosinante on Minion Island.
Even though it was just a simple meeting, his upbringing in the Hyūga clan had instilled in him the habit of being fully prepared at all times—ready to enter battle at a moment's notice.
So before every use of the Void Walker's Gate to travel to the One Piece world, he prepared everything.
Weapons, food, medicine, water, and various survival and combat essentials.
All sealed in scrolls, carried with him at all times, ready for anything.