How a Mom of Two Turned High-Dividend Stocks Into a ¥500 Million Fortune—All From Her Smartphone

From ¥2.4 Million in Initial Capital to ¥500 Million in Assets! Choruko, the featured investor in this article, is a part-time investor who made headlines after becoming a billionaire in yen while on maternity leave. Her investment journey began with anxiety about the future following her husband’s retirement and her own pregnancy.

Her journey was anything but smooth: grueling trading sessions while caring for her child and operating a smartphone with one hand, desperate days when massive losses left her bedridden, and an unbreakable mindset forged during a period of extreme poverty when she lived on just ¥100 a day. We trace her turbulent journey through multiple career changes and the hardships she endured before ultimately surpassing ¥500 million in assets.

¥2.4 million turns into ¥15.84 million

Choruko first began investing in stocks in 2011, when she was a university student. However, it was her father who had opened an account in her name, and she used money he had saved there as child support to purchase shares of Oriental Land.

After that, she lived a life with little connection to investing. But after starting her career, getting married, and later facing a situation in which her husband had to leave his job due to adjustment disorder, she took stock of her own assets. She discovered that the value of the Oriental Land shares she held in her brokerage account had grown to an astonishing amount. What she had purchased for ¥2.4 million had increased to ¥15.84 million by 2018, roughly seven years later.

“That was when I truly realized how powerful stock investing could be. My husband was able to return to work at a new company, but I was pregnant and knew I would be going on maternity leave. At the time, a consumption tax increase had also been decided, and there was a sense that the economy was likely to deteriorate. I felt that from then on, I would need to grow my money through stock investing, so I began seriously studying investing.” — Choruko, as quoted below

¥50 million in just six months! The trap of feeling invincible

The following year, in 2019, Choruko began maternity leave for her first child and entered the stock market in earnest. Her strategy of concentrating on a single stock and repeatedly buying and selling it throughout the day—a method known as day trading—proved remarkably successful.

While caring for her baby, she would operate her smartphone with one hand and place buy and sell orders with the other. At the peak of her maternity leave, she sometimes made more than 1,000 trades in a single month, and her assets reportedly grew to around ¥50 million in just six months. Her trading continued to progress smoothly overall, even weathering events such as the “COVID-19 crash,” and in January 2021, she finally reached ¥100 million in financial assets.

“I think I was making around ¥500,000 every day. At that point, I had this kind of sense of omnipotence, feeling that I had a real talent for investing. That overconfidence would eventually lead to a major failure, though.”

A ¥24 million loss in a single day—and despair

After becoming a millionaire investor, Chyoruko shifted the focus of her trading toward emerging growth stocks in pursuit of even greater profits. Her strategy worked to some extent, and her performance remained excellent. However, when she concentrated her investments in shares of AI inside, one of those high-priced emerging tech stocks, the stock price plunged following the company’s earnings announcement, resulting in a ¥24 million loss in a single day.

“I think I had completely adopted a gambler’s mindset, without any real basis for my decisions.”

She says she was so devastated by the massive loss that she stayed in bed for an entire day.

“After learning firsthand about the risks of emerging stocks, I decided to return to focusing mainly on large-cap stocks. Even so, I couldn’t keep up with changes in the stock market environment, and I struggled to get results. By July 2021, my assets had fallen to ¥68 million, so I decided to close out all my positions for the time being. In other words, I had left the stock market.”

Going all-in on high-dividend stocks and reaching ¥500 million

However, her return to the market came just a few weeks after this retirement. After learning that Mitsui O.S.K. Lines’ dividend yield had reached 10%, she instinctively thought, “I could live without working if I just relied on the dividend income,” and invested all her assets in Mitsui O.S.K. Lines stock.

The stock then surged, and her assets quickly recovered to ¥88 million. Having regained her momentum through Mitsui O.S.K. Lines, Chyoruko once again set her sights on becoming a millionaire investor. Around the same time, her roughly two-and-a-half-year maternity leave was also coming to an end (she had given birth to her second daughter after her first).

From there, she changed careers in order to balance raising her children with work, moving through an internal transfer, a job change, and eventually starting her own business. Along the way, she also continued to evolve her trading style. Her assets reached ¥100 million again in 2022. After that, she passed milestones of ¥200 million and ¥300 million with each passing year, eventually exceeding ¥500 million in 2026.

How did Chyoruko develop the indomitable mindset that allowed her to overcome devastating losses and the threat of being forced out of the market, ultimately building assets of ¥500 million?

The paid “FRIDAY subscription” goes into greater detail about her diversified investment strategy, designed with the risk of future bankruptcy in mind; the surprising money-saving rules behind her ¥100-a-day lifestyle, developed during her days of extreme financial hardship; and the three specific stocks she is currently watching that provide her with peace of mind in daily life.

▼ Chyoruko — She majored in pharmacy at university and, after graduating, joined a foreign pharmaceutical company as an MR (medical representative). She later worked in public relations for a listed company before becoming independent. She is now a part-time investor who runs a PR support business, including corporate PR and IR, while also investing in stocks. She is a mother of two. She began investing seriously in stocks in 2019 and reached ¥100 million in assets as early as January 2021. After experiencing several ups and downs, she established a style of large-cap swing trading based on the “Sakata Five Methods.” As of 2026, her assets have surpassed ¥500 million. She is the author of “Stock Investing: How a Mom Investor Saved ¥100 Million During Maternity Leave” (Diamond, Inc.) and has appeared in various financial magazines and economic programs.

 

■ Purchase “Stock Investing: How a Mom Investor Saved ¥100 Million During Maternity Leave” (Diamond, Inc.) here.

■ Chyoruko’s X (formerly Twitter) account is here.