Kakarot—also known as Son Goku—comes from the world of Dragon Ball. He's a Saiyan raised on Earth.
Saiyans are a warrior race that thrives on battle. They live for combat, take pride in strength, and fight until they drop.
They once served under Frieza, the tyrant emperor of the universe. But fearing a prophecy (and maybe due to a certain God of Destruction's suggestion), Frieza destroyed Planet Vegeta, the Saiyan homeworld. Only a handful of Saiyans survived—and some made it to Earth.
This was a world where people casually blow up the moon in early arcs (looking at you, Master Roshi and Piccolo), then go on to destroy entire planets mid-series (shoutout to Frieza's Planet-Busting Death Ball), and eventually just start nuking solar systems and realms of existence like it's Tuesday.
Compared to that, the Naruto world's strongest could maybe seal a single moon… once.
Honestly, even a low-level Frieza soldier might be able to wipe out the whole Hidden Leaf Village without breaking a sweat.
While Konoha's top-tier shinobi are still striking poses on Earth's surface, the Dragon Ball cast has been blowing up planets like party balloons.
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So that brings us to one very obvious question:
Why the hell is Kakarot sealed inside my body?!
Where's Kurama, the Nine-Tails?
Did he get one-shot by Goku's mouth beam?
…or worse, eaten?
Naruto squinted into the dim light, trying to peer through the massive iron gate, hoping for a glimpse of that familiar fox-shaped monster.
But no matter how hard he searched, there was no sign of Kurama.
> How does something that huge just go missing?! That fox was supposed to be my cheat code!
> "Uh… Mister Kaka—er, I mean, Mr. Son," Naruto called out anxiously, waving toward Goku. "Have you seen a really big fox around here?"
Goku tilted his head and scratched it.
> "Big fox? Nope. Haven't seen one. Just me in here. Oh—and I'm dead."
He pointed to the glowing halo above his head.
> "See this? You only get one of these after you die. Funny… you don't have one. Why not?"
> Because I'm not dead.
Naruto tried to stay calm. "So... why are you here then?"
> "Beats me!" Goku shrugged. "Last thing I remember, I was training on King Kai's planet. Took a nap, and boom—woke up in this weird place. Isn't this the afterlife? Feels pretty gloomy…"
> The afterlife? But this is my mindscape—my inner seal…
> "Anyway, I've got to keep training! There are two super-powerful Saiyans heading to Earth soon. Can't wait to fight them!"
> "But man, the gravity here sucks compared to King Kai's place. I'm getting rusty!"
He kept going. And going. Like a chatty old lady.
But as Naruto pieced together what he was hearing, he realized something:
> This Goku must be from early Dragon Ball Z. He probably just sacrificed himself taking Raditz down and started training with King Kai.
> So this is pre-Vegeta, pre-Namek…
> Okay. That tracks.
"Mr. Son, can't you leave the cage?" Naruto interrupted.
Logically, Kakarot should've been able to slip through the bars. Kurama was too big, sure—but Goku? He could just walk out, right?
> "Tried it," Goku muttered with a pout. "But there's some kind of weird energy blocking me."
He folded his arms, clearly annoyed.
> Something strong enough to stop Goku, even early-Z Goku? That's gotta be a power level over 4,000…
> Since when was this sealing jutsu that powerful?!
Naruto circled the seal again, searching for any sign of Kurama—but there was nothing.
He plopped down on the floor, defeated.
> No fox. No cheat code. No tailed beast chakra. Great.
> Technically, as a member of the Uzumaki clan, I should have a huge chakra reserve on my own. Even without Kurama, I should have at least a few dozen cards in the deck… right?
> And with no fox chakra interference, maybe my growth will actually be faster
Thinking that, Naruto felt a little better.
> "Hey, kid, what's with the mood swings?" Goku asked. "You were all gloomy, now you're smiling. Weird!"
> "Hey, got any food? My stomach's gonna eat itself at this rate!"
> You're dead, dude. Dead. Why are you still obsessed with eating?!
Naruto stared at him with a look of despair.
> Totally useless. What, am I supposed to become a Saiyanchūriki now? Or a Super Saiyajin-chūriki?!
> Saiyans don't even have chakra! He doesn't belong in this world!
No chakra.
No tailed beast.
No cheat code.
No hope.
…
Wait.
Naruto's eyes drifted to the gi on Goku's chest, where the bold "亀" (Kame) symbol was stitched.
His eyes lit up.
> I didn't lose a cheat code… I just got a new one!
Who was Kakarot?
Only the main character of Dragon Ball.
A guy who started with a power level of 2, and through pure sweat and training, rose to become the strongest in the universe.
A martial arts god.
He punched emperors, kicked androids, outclassed gods, and beat Majin Buu.
He had more techniques than most shinobi could name:
Afterimage Technique
Ki control
Kamehameha
Flight
Kaio-Ken
Spirit Bomb
Every single one of those could be a god-tier technique in this world.
Even if this Goku wasn't his final form yet, he was still the strongest guy on Earth.
If Naruto could just learn a little…
His growth would skyrocket.
A good mentor could be just as powerful as a cheat code.
> Forget "traveling old man in your head"—I've got the strongest fighter in another universe living in my gut!
Naruto's eyes sparkled like treasure.
> "Mr. Son!" he suddenly shouted, standing upright and bowing at a full 90 degrees. "Please accept me as your student!
> "Huh?" Goku blinked, confused.
For a moment, he was taken back. His memory flashed to ten years ago—a little bald kid arrived on a boat and said the exact same thing, in the exact same tone.
But that time, the kid was talking to Master Roshi.
This time…
He was the master.
> Man, that brings back memories…
Before he even realized it, he blurted out:
> "Sure!"
Naruto beamed, immediately calling him Sensei.
Goku waved it off casually—still a bit confused, but not bothered.
> In my short life, I've learned one truth: ninjas have limits. But… martial artists can BIU-BIU-BIU from the sky. So yeah, I'm done being a fragile ninja. Bye.
> "Hey, your voice sounds just like a friend of mine," Goku said thoughtfully. "He didn't have a nose or hair though. Do you know him?"
> You mean Krillin? The walking sacrifice who dies every saga?
> Yeah. I know the type.