Chapter 85
After Big Sis's high school lecture ended, we praised her to the skies and hugged her tightly.
Then Big Sis laughed brightly with a "Nihihi-."
She must have felt as if she were floating through the air after receiving so much applause from the high school students.
I can't lecture like Big Sis, so later I want to enter another competition, win a whole bunch, wear a medal around my neck, and get lots of applause too!
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We returned to our ordinary daily life.
It was a scorching-hot summer day, with the sun blazing down.
Ssshhhk-!
"Eek! You little rascal, Big Sis-!"
"Heeheehee, take that, Big Sis!"
I had a water-gun fight with Big Sis at the playground.
While click-click-loading our water tanks.
Swoosh-.
The water I shot soaked Big Sis's T-shirt.
But Big Sis wasn't easy prey, either.
She hid behind the slide, then, the moment I let my guard down, splashed me-!
"Hehe! It's cold!"
I ran away, laughing merrily.
It was hot enough to make sweat trickle down my face, but getting sprayed with water felt wonderfully refreshing.
Big Sis said there was a reason she had been exercising so hard lately.
Apparently, stamina was super important if she wanted to become a professor.
So these days, Big Sis spread out a yoga mat at home and followed along with gymnastics exercises, and she had also started playing at the playground with me much more often.
It was so much fun playing with Big Sis!
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These days, besides chess, I was learning all sorts of other games, too.
Go, Othello, and even Gomoku! Big Sis said playing a wide variety of classic games was good for brain development.
Hehe.
Actually, I was better at these games than Big Sis.
Whenever I looked at the board just once, I could instantly sense where the pieces should go.
But Big Sis said there was one unfortunate problem.
Classic imperfect-information games had age restrictions, so we couldn't play them yet.
"Why not?"
"It's because games where you hide your hand have been associated with gambling since long ago. Gambling is bad! Arin isn't going to do anything bad, right?"
"Of course not! I won't do anything bad!"
"Good answer, Arin. Still, there are tournaments for mahjong and poker that remove the gambling aspect and turn them into sports... But they're not very accessible here, and even overseas they strictly restrict participation to people eighteen and older. At your age, Arin, you'd have to wait about fourteen years. Though with your talent, you might be able to become a professional gamer or professional poker player someday."
"Fourteen years? That's super far away! Even if I lived three more times as long as I have so far, it wouldn't be enough!"
"Exactly? So forget what I just said. The games children are allowed to play are things like chess and Go, plus the Pokémon card game you're playing with Big Sis right now. The Pokémon card game is fun, too, right?"
"Yeah!"
I optimized my strategy while playing Pokémon cards with Big Sis by calculating the probabilities.
I considered when to play each card and guessed what cards Big Sis might have in her hand by then.
By the way, Big Sis said there was something called Yu-Gi-Oh!, too, but the pictures looked scary, so I said I didn't want to play it.
Pikachu was much cuter!
✒️✒️✒️
Anyway, these days I played board games with Dad, who had quit his job and now had lots of free time.
"Arin, Dad's going to win this time!"
"Not a chance! Dad, there's an opening right here!"
"Hehehe... My daughter, you're too good. Dad isn't someone to be pushed around, either, but I just can't beat you, Arin."
Even though Dad kept losing to me, he grinned from ear to ear and asked to play again.
It was nice being able to play so much because Dad didn't have to go to work.
It really was nice.
But still...
Big Sis had been spending less and less time playing with me lately.
"Big Sis, can't you play with me today, either?"
"Sorry, Arin. Big Sis has been a little busy lately..."
For some reason, I felt like Big Sis was growing just a tiny bit distant from me when she said that.
Big Sis, these days,
would borrow Mom's phone from here and there and chat away on the phone.
"Yes, President of Seoul National University! Oh, that document-"
"You're going to issue my faculty number? Yes, yes, understood-!"
Something about Seoul National University and something about being a professor.
I knew it was an amazing place, but I didn't really understand the details.
Big Sis handled her calls briskly, like an adult.
And she had also started going out with Mom much more often.
"Arin, Big Sis is going out with Mom for a little while!"
"Okay... have a good time."
"Dad and I will take good care of the house."
Click-.
After the door clicked shut, my heart felt strangely empty.
That night.
I lay in bed and hugged my beloved teddy bear doll, Popo, tightly.
"Popo..."
Popo couldn't say anything.
Still, Popo listened well whenever I talked and made a good friend because he was soft and fluffy to hug.
"When Big Sis becomes a professor next year, she won't be able to play with me anymore, right?"
Squeeze-!
I hugged Popo even tighter.
"If I can't play with Big Sis... I think I'll feel a little lonely."
Honestly.
My chest felt tight somehow because it seemed like Big Sis kept getting farther away from me.
We used to stick together and play all day long.
But these days, Big Sis kept hurrying off somewhere or other.
"…"
When I buried my face in Popo's soft, fluffy belly, a few tears slipped out.
But then.
Suddenly, I remembered what Big Sis had said in her TV interview.
Our whole family had watched the part of the broadcast featuring Big Sis over and over, so I remembered it vividly.
— I think children should grow up doing only the things they like.
So Big Sis was now
working this hard because she wanted to do the thing she liked best in the whole world: mathematics.
Thinking about it that way,
I felt like I shouldn't cling to Big Sis.
I sprang up and sat Popo down beside me.
"Popo. I've made up my mind."
Our super-genius Big Sis was doing what she wanted to do.
Then I had to cheer her on bravely!
"I can't stick to Big Sis forever, either!"
I clenched my little fist tightly.
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The next day.
I scampered over to Big Sis.
"Big Sis!"
"Huh? What is it? What's wrong, Arin?"
Big Sis looked at me with a slightly cautious expression.
She had probably seen me looking so gloomy yesterday.
But I had already finished preparing myself mentally!
I threw my arms wide and rushed into Big Sis's embrace.
"Big Sis, I'm okay! I'll cheer you on when you become a professor!"
"... Arin."
"It's what our super-genius Big Sis wants to do! Even if I can't play with Big Sis anymore, I can still play nicely with Dad!"
When I said that,
Big Sis looked surprised for a moment, then pulled me into a tight hug.
"... When did our Arin become so thoughtful?"
Pat-pat-pat-.
Big Sis gently stroked my hair.
Hehe. Big Sis's touch was always so warm.
... Honestly, I was a little lonely.
But so what?
If Big Sis was happy, then I was happy, too!
"... But Arin, there's one thing you're misunderstanding."
"Huh? What is it?"
"Big Sis is going to keep playing with Arin~"
"Huh?"
"Even if Big Sis becomes a professor, all she'll do is leave early in the morning and come home before dinner. I might even get home earlier than Dad did when he occasionally worked late! And honestly, on days when I don't have any lectures, I don't even have to go to work!"
"Huh, whaaat...?"
"So don't worry too much. Of course, compared to before, we'll have less time together... but we'll still be able to spend more than eight hours together every day."
"Hee, hehee... Is that so?"
"Was our Arin feeling down because she thought Big Sis might leave somewhere far away?"
Pffft-.
My face suddenly felt hot.
Zoom-zoom-zoom-!
I immediately ran into Mom and Dad's bedroom and locked the door with a click-.
"Ah! Arin, where are you going?"
Knock. Knock. Knock.
Big Sis realized her mistake and knocked on the door from outside, but
Hmph! I wasn't coming out until I felt better!
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Phew.
That was tough, cheering Arin up...
Apparently, Arin didn't really know what a professor did and had mistaken it for Mom and me going somewhere very far away and never coming back.
Arin had seemed to understand during the family meeting as she nodded along, but once I started getting frequent calls from Seoul National University, her anxiety must have grown.
However.
There was no denying that Arin's daily life of staying home with Mom and me all day would change significantly.
Next year, Mom and I would have to commute, and Arin would have to stay with Dad.
If she felt anxious about those changes in her surroundings, it couldn't be helped.
All I could do was play with her a lot, until she felt that she wasn't lacking any love...
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Of course, Arin didn't spend all day playing board games.
Since we had chosen homeschooling instead of sending her to kindergarten, we also taught her Korean, English, and mathematics whenever we had the chance.
Dad handled Korean, Mom handled English, and I handled mathematics. The three of us divided up the work and took turns teaching Arin.
Arin had the talent to spread her wings across the world someday, after all.
If she mastered English in advance while she was young, things would be much easier for her later.
Fortunately, Arin had a memory far superior to that of other children her age, so she rarely forgot vocabulary once she learned it and quickly made it her own.
She sometimes grumbled that studying mathematics gave her a headache, but since her favorite Big Sis taught her personally, she followed along quite well, and I was grateful.
I'd even compared her to a human computer, after all.
By now, she could casually solve complicated determinants with a quick mental calculation.
Ah, speaking of matrices reminded me of something.
Apparently, high school students don't learn matrices in the current curriculum.
They even choose one of calculus, probability and statistics, or geometry for the College Scholastic Ability Test?
That was just ridiculous.
In South Korea, a country that prided itself on being a technological powerhouse, that simply wasn't acceptable.
In this age of AI, with Big Tech working itself into a frenzy to develop semiconductor chips that could process matrix calculations insanely fast,
how could the talents of the future not even know that matrices existed?!
And then, suddenly.
I realized something and got goosebumps all over.
The freshmen in the Department of Mathematical Sciences whom I would be teaching next year
might enter university without even knowing what matrices were.
"... Ugh."
I couldn't help sighing as I pressed a hand to my forehead.
Would I have to teach them matrices one by one first?
My future was already starting to look bleak.
In fact, there were mountains of things I wanted to nitpick about South Korea's educational policies.
But here, I should end by quoting Fermat's famous saying.
— I could talk about this problem all day, but the margin is too narrow, so I'll stop here.
✒️✒️✒️
Time passed, and it was November 2026.
Before I knew it, the day of the College Scholastic Ability Test had arrived.
It was the day the older students who would enter college next year took the CSAT.
Normally, around this time of year, there should have been a frightful chill in the air, cold enough for snow to come pouring down.
Strangely, this year the weather felt more like autumn, with only a slightly chilly breeze blowing.
That day, I stood side by side with Dad and Arin in front of a nearby high school that had become a CSAT testing center, bundled up in warm outerwear.
Of course, I wasn't taking the test.
And naturally, neither was Arin.
You want to know why we were there?
"Eun-chae!"
"A-yeon! Arin!"
Someone close to us was taking the CSAT here, so we had come to cheer her on in person.
According to what Eun-chae had told me, she was aiming for Seoul National University's Department of Mathematical Sciences!
Her choice of career was so admirable.
There was no way I could keep from coming to cheer her on.
"Eun-chae, have this."
Glug-glug-.
I opened the lid of the cute pink thermos I was carrying and poured some into a paper cup.
Steam curled up from it.
"It's hot chocolate. I made it nice and sweet."
"Oh! Thank you!"
"Heehee. It's a thank-you for always giving me so many snacks."
Eun-chae wrapped both hands around the paper cup and took a slurping sip.
"Ah, it's warm..."
"Right? Right?"
"With A-yeon cheering me on, I feel like I can power through the CSAT!"
"Eun-chae, you can do it!"
"Thank you, Arin!"
Just moments ago, Eun-chae had been so nervous that she was walking stiffly.
But after hearing Arin and me cheer her on, she trotted briskly into the testing center.
I waved goodbye as I watched her back disappear.
✒️✒️✒️
And that evening.
[A-yeon! I think I did really well on the CSAT! Thank you!]
A message came from Eun-chae saying she thought she'd done really well.
And a month later.
[A-yeon, I got in! Seoul National University's Department of Mathematical Sciences!]
The news that she had finally gotten into exactly where she wanted to go arrived, too.
Arin and I celebrated Eun-chae at the chess club.
"Eun-chae, congratulations on getting in!"
"Eun-chae, you're the best!"
"Hehe, it's all thanks to Professor Yoo A-yeon! See you at school next year!"
Eun-chae, bursting with excitement, scooped me up and spun around in a circle.
"Eek! Hehehe!"
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And then time shot by like a railgun.
2027.
I became a kid who was legally required to attend elementary school.
... Of course, I wasn't going to attend. I'm just saying that, legally, that's what I was now.
The superintendent had created an achievement assessment just for me.
Apparently, if I passed that one test, I could skip all six years of elementary school.
And then.
February 26, 2027.
At last, the day arrived.
I attended Seoul National University's ceremony for presenting appointment certificates to new faculty and received my faculty appointment certificate directly from the university president.
— The faculty members whose names are called from this point on, please come forward.
The other professors before me were called up, received their appointment certificates, and were greeted with rounds of applause.
— Professor Yoo A-yeon.
Totter-totter-totter-.
When my name was called, I climbed onto the stage with my tiny steps.
In the middle of the audience, Mom, Dad, and Arin were waving at me with bright smiles.
"I hereby present the faculty appointment certificate to Professor Yoo A-yeon."
The president held the certificate in both hands and approached me.
But since I was still only 118 centimeters tall,
the president bent all the way down at the waist to hand me the certificate.
I'm sorry for mistaking you for someone with a heavy bottom last time, Mr. President. I didn't expect you to bend even your back this far for me.
I politely accepted the appointment certificate with both hands.
…………………………………………………………
Appointment Certificate
Yoo A-yeon
The aforementioned person is hereby appointed as a faculty member of Seoul National University's Department of Mathematical Sciences.
…………………………………………………………
"Thank youuu-!"
I hugged the stiff appointment certificate tightly.
The mathematics that Professor Shin I-jun had loved so dearly during his lifetime.
And the mathematics he had been certain made Yoo A-yeon's heart pound.
I took my first step along that path once again.
This time, however, I wasn't alone.
I had Mom, Dad, and Arin.
Click-! Click-!
Flashes went off.
The image of a six-year-old little girl smiling brightly while holding her faculty appointment certificate was captured on camera.
And I.
became an elementary school girl professor!