Chapter 5: Me vs. Math, Machines, and Mystery Rectangles
POV: Ren Kisaragi (a Ninja stuck in the 21st century with absolutely no clue how Wi-Fi works)
"Kaito, don't push yourself too hard."
That voice—so calm, so mom—came from the living room. I froze for a second, mid-chew on an apple slice, because the last thing I wanted was to sound suspicious. You know how moms have that superpower of instantly knowing when you're about to lie? Yeah, no pressure or anything.
"Yeah, Mom," I said, my voice probably too chipper. "I'm taking it easy. I just made new friends."
Okay, not exactly the full truth—I was trying to take it easy, and sure, I did make some new friends, but mostly because I was desperate to stop staring at the ceiling all day.
Miki, the real mom of this body, gave a soft smile from the couch. "That's good. Are they from around here?"
"Yeah, the Fujimoto family," I said, trying to sound casual like I wasn't rehearsing every word in my head. I pulled out a packet of juice and a couple of apples to munch on, hoping food diplomacy would cover any weird vibes.
Miki paused, thinking. "I don't think I've met them before. You should invite them over sometime, okay?"
Smooth, Mom. Way to casually drop social expectations on a guy who's struggling not to accidentally reveal he's not actually your son.
"I will," I said, trying to sound confident as I practically bolted upstairs. A ninja never lingers after a social invitation.
From the living room, Miki chuckled softly and went back to her TV show, shaking her head just a little.
My son has grown, she thought, and he's making me feel needed again.
She didn't know the half of it.
Okay, so picture this: I'm sitting cross-legged on the floor of Kaito's room, sipping on a juice box like a five-year-old while munching apples like they're rations on a solo mission. In front of me? A history book. Not a fun one about epic battles or famous ninja—nope. Just dry, printed words about dates and treaties and revolutions I didn't even know existed.
If boredom could kill, I would've flatlined ten pages ago.
"This is worse than low-rank missions," I muttered, flipping another page and pretending to care about the Treaty of Versailles. I mean, it didn't even sound like a place you could punch. Where's the drama? The action? The explosions?
Still, I kept reading, half-heartedly highlighting random sentences like I knew what I was doing.
I didn't.
Then my eyes wandered around the room and landed on… it.
The black screen sitting on the desk.
I knew it was called a computer. Sage Yun Che had introduced enough Earth inventions back home that things like televisions, phones, cars and electricity weren't exactly mysteries to me.
Computers, though?
That was another story.
Apparently, it was a box that could find almost anything—if you knew how to use it. Which, spoiler alert: I didn't. Not even close.
Then there was that smaller rectangle beside it with buttons all over it. Some kind of control device? Part of the computer? A really complicated writing board?
I had no clue.
So far, I'd avoided touching too much in fear I'd accidentally delete something important or somehow break the entire thing just by pressing the wrong button.
Don't laugh.
With my luck, it was possible.
Anyway, back to the present.
I rubbed my temples and sighed, flipping through more of Kaito's schoolbooks. Math? Looked like forbidden Sect scrolls. Science? Might as well have been written in another language.
The only thing I managed to understand was from the general studies book, which explained—finally—what a computer was supposed to do.
"A gateway to information," it said.
Great.
So it was basically a giant library.
Except somehow everything was inside a screen.
I'll have to ask Haruki to show me how it works, I thought, mentally noting to find a way to do it without looking like a total idiot.
I mean, what was I supposed to say?
"Hey, can you teach me how to use this thing because I'm a body-swapped ninja from another universe and computers are scarier than Hell Creatures?"
Yeah.
Nope.
Still, at least I wasn't completely off the mark.
I was right, I thought with a smirk. There's no way I'm passing anything in this world without a teacher. Or five.
One thing was certain—I was going to need help.
A lot of it.
Preferably from someone patient enough to explain how to use a computer without calling the fire department.
"So I was right in assuming I was going to fail without a teacher," I muttered dramatically, as if I were some tragic hero on the brink of defeat. Then I stood up like I was about to duel destiny itself. In reality, I took what's known in the Veiled Moon Sect as the Academy Stance. You know, knees bent, hands up, serious face—but with a juice box still on the desk. Very intimidating.
I stared at myself in the mirror on the closet door. I looked like a guy about to karate-chop algebra in the face.
This was the basic fighting style every Ninja learned at the Academy. And even though I hadn't used it for real in what felt like forever, it was burned into my muscles. Still, there was one teeny-tiny problem: this body—Kaito's body—was not exactly battle-ready.
I stretched one leg out, feeling confident.
It trembled.
I threw a lazy punch.
My shoulder popped like a rusty door hinge.
Yeah. I was basically trying to upload high-level ninja data into a potato.
But I wasn't giving up. Nope. That's not the Ren way.
I went through the easier moves first: stance shifts, basic punches, a few kicks that wouldn't qualify as embarrassing. Each movement was sharp in my head, but my muscles acted like they were learning to dance blindfolded in roller skates.
"Come on, body! You've got legs, arms, and zero kunai wounds. We can do this!"
The key was repetition. Every Ninja knew that. The more you practiced, the more your body stopped thinking and just did. Like how I could eat noodles with chopsticks blindfolded while dodging throwing knives. (Don't try that. Very specific training.)
Bit by bit, I started adding in some of my personal flair—the little adjustments I'd come up with during real fights. A sideways step into a spinning elbow. A low duck into an upward palm strike. I even tried my signature "fall-back-then-kick-em-in-the-jaw" move.
It looked more like "fall-back-then-sprawl-like-a-dead-fish," but hey—baby steps.
After an hour of sweating, grunting, and occasionally yelling things like "Ow, my spine!" and "This was easier when I had Ki!", I finally collapsed face-first onto the carpet.
Victory? Sort of.
Defeat? Definitely.
"It's only… twelve?" I croaked, rolling over to see the clock blink 12:03 PM like it was mocking me.
So yeah—half-dead from ninja yoga, and the day wasn't even halfway over.
On the plus side, I hadn't broken any bones, windows, or furniture. On the downside, I was pretty sure my hamstrings were plotting revenge.
Still… there was something kind of nice about it. The quiet. The effort. The tiny progress.
It was like I was building myself up again, piece by piece. Even if the pieces were a little sore and whiny.
One step at a time, I reminded myself as I stared at the ceiling and willed my limbs to stop vibrating.
And then I reached for another juice box. Because training might be hard, but hydration is still the number one rule of survival—Ninja or not.
"What should I do?" I muttered, dramatically flopping onto the bed like I was in a soap opera. "Can't train—my legs feel like jelly. Can't read—my brain feels like jelly. I'm basically a jelly."
I sighed.
Seriously, how did normal teens survive this kind of boredom without throwing kunai at walls?
Then, it hit me.
The TV.
I knew what televisions were. Sage Yun Che had introduced them back home years ago, along with phones, cars, bikes, electricity, and a bunch of other things from Earth.
The Veiled Moon Sect just didn't have any.
So naturally, I was curious.
I'd seen Miki using it a couple times—pressing buttons and changing channels. I understood what it was supposed to do.
Using one myself?
Different story.
Only one way to find out.
I ninja'd—okay, walked like a tired human being—down the stairs and peeked into the living room. Empty. Score!
I dove onto the couch like a pro and grabbed the remote. Yeah, I knew it was called that. I was basically a tech genius now.
I pressed the red button like I'd seen Miki do, and bam!—light, sound, drama.
The screen came to life showing some guy crying in the rain while a girl stared dramatically into the distance, clutching a scarf. There were tears. There was music. There were at least three slow zooms.
"What kind of show is this?" I whispered.
After two minutes of watching people dramatically not say what they were thinking, I clicked the arrow button. Another channel. A guy yelling about taxes. Click. A cooking show—interesting, but now I was hungry. Click. A news anchor talking about a cat that stopped traffic.
"People watch this stuff on purpose?" I muttered. "Do they not have forests to train in or dangerous criminals to chase?"
Click.
And then…
Boom.
GIANT. FIGHTING. ROBOTS.
Flying through space.
Shooting lasers.
Punching meteors.
"WHAT IS THIS GLORIOUS MADNESS?" I gasped as I sat up straighter than I had all day. My eyes were glued to the screen as two massive metal warriors clashed, their weapons glowing, the background exploding in fireworks of sci-fi mayhem.
"Titan Frames?" I read the title out loud. "Are those like armored war constructs or something?"
I was completely entranced. They had backstories. They had rivalries. They had poses. And don't even get me started on the music. It was like Ninja battles but in space—with better hair.
One episode turned into two. Then three. Then the show changed—and suddenly it was Dragon Warriors Z.
"Wait. He just screamed for five minutes and now he's glowing? That's a power-up move?! I need that. I need that in my life."
I sat there for hours, my mouth open in awe, as spiky-haired warriors blew up mountains with energy blasts and flying kicks.
Television was way better than I expected.
It was a treasure trove of techniques, strategy, cool outfits, and power-up screams. Honestly, I could probably write a thesis on the tactical value of watching anime if I knew what a thesis was.
The front door clicked open and Miki came home.
She poked her head into the living room and saw "Kaito"—that's me, still undercover, remember?—lounging on the couch with anime eyes and crumbs on my shirt.
"Back to your usual anime binge, huh?" she chuckled, walking past like this was just another normal day.
I gave a nervous laugh and nodded. "Yeah… totally my usual…"
But in my mind?
So many techniques. So many ideas. So much yelling.
Yes.
This TV...
Was one of the greatest teachers I'd ever met.
Well, besides Master Jin.