Naruto: How to Be an Undercover Shinobi

With the help of Katsuyu's mucus, Reiji sat cross-legged on the ground and quickly sensed the so-called natural energy.

At that moment, he noticed something strange.

His cells weren't just absorbing natural energy—they were also releasing it.

This…

This was seriously messed up!

Usually, only things like trees or rocks both absorb and emit natural energy.

No wonder Katsuyu-sama had said he shouldn't be running around on two legs.

By now, Reiji didn't even know what he was anymore. But he didn't really care. As long as it didn't interfere with eating or slacking off, who cared?

Sitting calmly in the middle of Shikkotsu Forest, Reiji continued absorbing the natural energy that filled the area.

Before long, he felt full.

...

Outside, Tsunade watched his current state, stunned, covering her mouth in shock.

"It's okay, Lady Tsunade. If my senses aren't mistaken, he'll be fine," Katsuyu said gently.

But Tsunade still stared at Reiji in disbelief, her heart pounding.

She watched as roots, grayish-brown and thick, slowly broke through Reiji's skin at the points touching the ground and pushed themselves deep into the earth. At the same time, his skin began transforming rapidly—hardening and turning into bark.

Soon, Reiji's entire body was gone. In his place stood a tall, straight tree trunk.

It had no leaves, no branches—just a massive trunk as wide as three people hugging it, rising straight toward the sky. At its top, a giant flower began to bloom, petal by petal.

...

Inside Reiji's consciousness, the monster slowly lifted its head and looked up at the sky. For the first time, its mouth, which had always remained silent, let out a raspy, furious roar.

"Don't wake up... Only one!"

"Don't wake up... Only one!"

"Don't wake up... Only one!"

...

Meanwhile, Reiji felt more comfortable than ever. A long-lost drowsiness washed over him. He wanted nothing more than to just sleep forever.

But then, the faces of Mizukuma, Rie, Tsunade, Amai, Jiraiya, and others flashed through his mind, all shouting at him in unison—

"Wake the hell up! It's party time!"

Their voices thundered through his consciousness.

Startled, Reiji jolted. A sudden burst of clarity flooded his senses.

Crap, I almost fell asleep!

Suddenly, a line from Tang Shen surfaced in his mind:

How can you even think about sleeping?

At your age? At this stage of your life?

Where's your drive?

A chill ran down his spine. Reiji snapped his eyes open.

...

Outside, Tsunade stood frozen, completely shocked by the transformation.

Just as the monster's roar faded from Reiji's mind, the enormous flower slowly closed its petals. The massive trunk—once proud and upright—began to bend, as though it couldn't support the flower's weight. Eventually, the flower pulled the tree down until it gently touched the ground.

The petals opened.

No fruit inside—just Reiji, cross-legged on the ground, butt exposed, with a bold tattoo of the character "hard" on his shoulder.

This was insane!

He literally planted himself... and then grew himself back!

Honestly, you couldn't get more ridiculous if you tried.

Reiji opened his eyes in a daze. He stared blankly at Tsunade, who looked like she'd seen a ghost, then turned to Katsuyu-sama, who was murmuring in awe nearby.

Wait...In awe?

Reiji's pupils suddenly widened. His perception sharpened to an extreme—everything around him became vivid and crystal clear.

With just a thought, the cells passively absorbing natural energy halted their function. The clarity instantly faded into a blur.

That... was Sage Mode perception!

A realization struck him—he really was suited to mastering Sage Mode!

While he was still lost in thought, the giant tree behind him crumbled into dust, drifting away in the wind.

And Tsunade came running over, cheeks flushed, and threw herself at Reiji.

"You scared me to death!"

As she spoke, Tsunade's mouth kept going nonstop.

"You turned into this huge tree—so big! I was almost scared to death!

Then, then your head bloomed! That flower was massive! Oh my god, and it was green! So gross!

And then you actually made yourself into fruit! You're so selfish!"

Seeing Tsunade suddenly act so childishly, and feeling the sincerity in her emotions, Reiji couldn't help but grin.

But his amusement didn't last even three seconds before he suddenly felt a chill on his backside.

Wait... where are my clothes?!

On reflex, Reiji tried to use the Flying Thunder God Technique to get out of there—only to realize he couldn't sense a single technique.

Seriously? In broad daylight?

His eyes darted around, then he awkwardly channeled Senjutsu chakra.

The next moment, his hair grew wildly and wrapped tightly around his body, concealing him entirely.

Looking down at his new "outfit," Reiji nodded in satisfaction.

Though... why the hell was his hair green?

Sensing his awkwardness, Katsuyu made a bit of small talk with Tsunade, then sent her back to Konoha.

Reiji, still bundled in green hair, looked up at the mountain-sized Katsuyu and gave a grateful nod.

"Katsuyu-sama, can I sign a contract with you?"

"Of course~" Katsuyu responded cheerfully.

Hearing that, Reiji's lips curled into a sincere smile.

At that moment, a summoning force activated. Reiji waved at Katsuyu-sama and responded to the call.

...

The next moment, Reiji reappeared in the Senju residence in Konohagakure.

Then, using the Flying Thunder God Technique, he returned to his bedroom and changed into a fresh set of clothes.

Finding a mirror, he looked at his current appearance and felt more than a little awkward.

How should he even describe this?

Naruto's Sage Mode had frog-like pupils, with orange-red markings on the upper eyelids and corners of the eyes.

Jiraiya's Sage Mode had straight and curved red stripes across his face.

The First Hokage had a circle on his forehead with a dot in the center, and orange-red shading under his eyes.

And Reiji? His hair turned green—and he had dark circles under his eyes.

Staring at his reflection, Reiji let out a quiet sigh and immediately shut off Sage Mode.

Green might be a noble color, representing hope and vitality... but sadly, it had been ruined by love.

And those dark circles? They might have looked serious—if only they hadn't been ruined by a damn panda.