Even Today, the Genius High School Programmer Cashes In on Day Trades, Completely Flustered by Beautiful Girls' Growing Affection. - Chapter 3: The Daily Life of a High-School Day Trader.

The Daily Life of a High-School Day Trader.

“Now then…”

Back home from the bookstore, I spread out the books I’d bought across my desk.

On the way I’d been half-braced for another run-in with those three guys, but thankfully nothing came of it.

Three volumes in total.

Two on programming, and one on stock investing—specifically, a book about systematic trading.

My desk held a mouse, a keyboard, and three 21-inch monitors.

The classic triple-monitor setup.

Across the screens stretched an emotionless grid: major Tokyo Stock Exchange indices, forex data, and candlestick charts for more than fifty individual stocks.

Yes—the “hobby that also turns a profit” I’d mentioned earlier was stock trading.

***

When I was still in elementary school, two things captured my interest with almost obsessive intensity.

One was programming.

The other was stock investing.

My father took me to a nearby programming school when I was in third grade.

Everyone else in the class was a middle- or high-school student.

We wrote commands—little instructions—onto what they called “electronic paper” on a tablet, combining them until letters and shapes appeared on screen exactly as ordered, or until the drawings we’d made began to move.

The thrill of that moment is still vivid in my memory.

What else could it do…?

I went to the library, borrowed thick books cataloging entire command systems, and started experimenting on my own.

The very next week I’d built a simple game that used the tablet’s gyro sensor: drop a ball while dodging obstacles.

I played it myself, grinning the whole time.

When I showed it to the instructor, he asked, “Which website did you download this from?”

He refused to believe I’d written it from scratch.

The school quickly became useless to me, so I quit.

Even so, I kept studying programming on my own, steadily tackling more and more complex projects.

It was also my father who first introduced me to stock investing.

He believed children should develop financial literacy early, so he opened a junior securities account in my name.

I picked up rough knowledge of accounting and stock markets from library books and online sources.

By fourth grade I could more or less understand the financial statements listed in quarterly reports.

My very first stock purchase came in the autumn of fourth grade:

a major company operating elderly care facilities.

Solid fundamentals, and with Japan’s aging population, demand was only going to grow.

That was my reasoning.

I used fifty thousand yen I’d saved from New Year’s gifts.

After that the share price climbed steadily.

Over four years it underwent three stock splits, and the value rose eightfold.

Maybe I just got lucky.

By spring break of my third year in middle school—right after high-school entrance exams—the fifty thousand yen had ballooned into eight hundred thousand.

In the meantime I’d studied price movements obsessively.

I began to notice that stock prices exhibited certain patterns.

Not perfect ones, of course—not one hundred percent reliable.

But if I could control risk and reward while trading in line with those patterns… maybe consistent profits were possible.

That quiet confidence took root.

So I decided to build my own automated trading program: a system that would monitor price action in real time and execute buys and sells when the right conditions appeared.

I begged my father to open a margin trading account in his name and let me use it.

Programmatic trading required both a margin account and access to the broker’s API—neither of which minors could get on their own.

I started running the system after entering high school.

The Tokyo Stock Exchange opens from 9:00 to 11:30 in the morning session, then 12:30 to 15:00 in the afternoon.

Naturally I’m stuck in class during those hours.

So I set the program once in the morning, and it trades automatically from there.

Twice a day—during lunch break and after 15:00—I check performance on my phone.

When I get home I tweak stock selections and parameters based on market conditions.

That’s the routine.

At first there were losses.

Gradually, though, the system found its rhythm and began delivering steady gains.

I still have losing days, naturally—but no more losing weeks.

The starting capital of eight hundred thousand grew to 2.3 million after one year.

Right now it stands at 3.8 million.

I’ve slowly increased position sizes, and my interim goal is to reach ten million by the time I graduate high school.

“…There. That should do it.”

After skimming the new books, I turned to the computer and fine-tuned the trading program.

The forex market was moving, so I adjusted a few candidate stocks.

Here’s hoping it earns its keep again tomorrow.

“Still… that girl today really was cute, huh…”

They say most boys in the throes of puberty feel their hearts race when they see a pretty girl—want to talk to her, date her, make her their girlfriend.

But I don’t experience that.

A lover? Going out? Sounds like a waste of time.

Those things always break eventually anyway.

When I looked at her, though… it felt more like admiring a flawless gem, a delicate flower, or some pure, untouched landscape.

A quiet appreciation. Nothing more.

“Well… guess I’ll never see her again anyway.”

Muttering to myself, I left the room.

Might as well take a bath…