I was five years old.
"Watch carefully, Leo."
Mom placed her right hand over the back of her left.
For a moment, nothing happened.
Then—light bloomed.
A faint glow spread across her skin, and from the Knight's Crest on the back of her hand, a sword emerged as if being drawn from thin air.
"…A sword?"
It wasn't a trick.
The blade wasn't pulled from a sheath—it formed, solidifying from light into dull iron.
"This is a Heraldic Sword," Mom said proudly. "A knight's proof."
It looked heavy. Crude. More like a lump of iron than a refined weapon.
Yet Mom swung it easily with one hand.
I'd wondered about it for a long time.
Where did that strength come from, in such a slender body?
As if answering my thoughts, she relaxed her grip.
The sword dissolved into particles of light and vanished back into the crest on her hand.
"…So it wasn't magic."
"Magic?"
She tilted her head. "Not quite."
I stared at her arm.
"This world really is different."
"What's the name of this country?" I asked.
She puffed out her chest.
"This is the Arcadia Sword Kingdom! One of the Five Great Powers!"
A name I'd never heard before.
Which meant only one thing.
"…So I really was reincarnated into another world."
I looked back at her crest.
"What exactly is that?"
Mom smiled faintly.
"This is a Knight's Crest. Those who bear one are called knights."
She tapped her bad leg.
"I fought on the battlefield once. This injury is from that time. I retired after."
So it was true.
She really had been a knight.
"Leo," she said suddenly, eyes sparkling.
"Do you want to become one too?"
"…A knight?"
"Swing a sword, defeat enemies, protect others—be a hero!"
She leaned closer.
"All boys admire knights, right?"
I didn't.
Not really.
But…
"…Yeah."
My voice was flat.
Mom, however, exploded with joy.
"Really!? I knew it! As expected of my son!"
She jumped despite her bad leg.
"Then we'll start training today! Special training!"
"…Special training?"
"Yes! With Mom!"
I sighed internally.
I wasn't interested.
But seeing her so happy…
"…Okay."
The garden.
I held a wooden sword.
"Come at me from anywhere!" Mom said confidently.
"…Won't you get hurt?"
She blinked.
"…Oh."
That didn't inspire confidence.
I swung.
The blade struck her—
…and stopped.
"…Huh?"
No pain. No impact.
"Why…?"
Mom tapped her arm.
"Crest power. Those with Knight's Crests can only be harmed by others with crests."
"…A rule of the world?"
"Mhm. That's why knights are strong."
A thin, invisible barrier. The force dispersing.
I tried again.
And again.
Nothing.
"When you're older, you can take the knight exam," she said.
"If you pass, you'll receive your own crest."
"…I see."
Power wasn't innate.
It was granted.
"Remember this," she said seriously.
"Only those with crests can defeat those with crests."
"…Got it."
Days turned into months.
Months into years.
Mom was strong—her movements refined by real battle.
I watched.
Copied.
Adjusted.
The way I always had.
I wasn't perfect.
Once, I overcommitted on a swing and tripped over my own foot.
Mom caught me before I hit the ground.
Laughing.
"See? Even geniuses fall."
…That helped.
Three years passed.
I was eight now.
"Leo," Mom said one day. "This will be our last duel."
"…Last?"
"If you win, you graduate."
We faced each other.
I raised my wooden sword.
"My name is Leo. With this name and my pride, I challenge you to a duel."
She smiled and mirrored me.
"My name is Nina. With my name and knightly pride, I accept."
I ran.
She blocked.
Her bad leg slowed her.
I circled, struck.
Blocked—but her posture broke.
Rotated. Struck again.
She countered.
I saw it.
Stepped in.
"...You really have grown strong."
My blade pierced her abdomen.
The crest stopped the damage—
—but it was a clean hit.
She fell backward into the grass.
"…Leo wins."
I stared at my sword.
I'd done it again.
I surpassed someone.
And usually—
That meant resentment.
I didn't want that.
I didn't want her to hate me.
But instead—
"Leo is a genius!"
"…Huh?"
She hugged me tightly.
Laughing.
"I'm so proud! This is amazing!"
"…You're not angry?"
"Why would I be!?"
"My child being strong makes me happy!"
My chest hurt.
Tight. Burning.
"…Because you taught me… I got stronger."
"…Thank you, Mom."
Her arms tightened.
"That's enough."
From that day on, sword practice became routine.
Mom stopped fighting—just watched.
Smiling.
"Hey, Leo."
"…What?"
"I love you more than anything."
"…!"
My swing missed completely.
She laughed.
I blushed.
I was happy.
I wanted to say it too.
But—
"Dinner's ready!"
"…Coming!"
Just a little longer.
Let me stay in this warmth.
Even if it's a lie.
The seasons turned.
My body and mind grew.
And then—
The day of my first real battle arrived.