Money coming in while you sleep.
It would be great if such a system existed, wouldn't it?
Actually, with Claude, this is now a reality.
Overseas, there are people using Claude to write e-books, selling them on Amazon's "Kindle," and receiving royalties almost automatically.
Moreover, if things go well, you can aim for 1.5 million yen a month.
Once you publish a book, it continues to sell on its own 24 hours a day.
Even while you are sleeping or playing, royalties come in.
Today, I will honestly explain how to build that system.
Furthermore, in the second half, I will talk about "back-end usage that earns even more than royalties."
This is the real core.
By the way, the backstories of "systems for earning with AI" like the ones discussed in this article are also shared in my open chat "X Operation Strategy Room."
Participation is free, so please take a look beforehand if you like.
▼ Open Chat "X Operation Strategy Room"
Let's get started.
What is "Kindle Publishing" in the first place?
First, let me explain briefly.
Amazon has a system called "Kindle Direct Publishing (KDP)" where individuals can publish e-books.
Anyone can release their own book for free without going through a publisher.
No inventory needed. No printing needed.
When your book sells, you get royalties.
Moreover, this royalty rate is amazing.
For e-books, if you set the price between $2.99 and $9.99 (approx. 450 to 1,500 yen), the royalty rate is a staggering 70%.
Compared to paper book authors who get around 10% royalties, it's in a different league.
For example, if one 1,500 yen book sells, about 1,000 yen goes to you.
Once published, this continues to happen automatically 24 hours a day.
This is the reality of "royalties while sleeping."
How much can you actually earn? (Real figures)
It sounds like a dream, but I'll show you the specific numbers honestly.
According to data from 2026 overseas:
・Well-crafted books
Per book: $50–500 per month (approx. 7,500 to 75,000 yen)
・With a collection of 5–10 books
$1,000–5,000 per month (approx. 150,000 to 750,000 yen)
・With 20+ books in profitable genres
Over $10,000 per month (over 1.5 million yen)
Here is the most important point.
Income is determined by the "number of books," not talent.
The data shows this clearly.
80% of people who have only published 1–3 books earn less than $100 (approx. 15,000 yen) per month.
But for those who have published 25 or more books, the median monthly income is $3,000 (approx. 450,000 yen).
In other words, it's like this:
If one book is a "small vending machine" that generates 7,500 yen a month, you increase that to 10 or 20 machines.
Then, the total becomes your monthly royalty.
Even if each book is small, if you stack them up, they become a large passive income.
And Claude is what makes this "increasing the number of books" task overwhelmingly fast.
Why it became possible with Claude
In the past, writing a book was hard.
You had to think of the structure, write tens of thousands of words, and it took months.
If you outsourced it, it often cost over 100,000 yen per book.
So, 20 books wasn't realistic.
But with Claude, it looks like this:
① Planning and Theme Selection
"Give me 10 book themes in the [Genre] category that are likely to sell on Kindle, in order of likely demand."
② Structure and Table of Contents
"Create a table of contents for this theme that will make readers want to read until the end."
③ Writing the Body
"Write the body text chapter by chapter according to this table of contents. Make it easy to read and include specific examples."
④ Title and Description
"Write a title that makes people want to click and a description for the Amazon product page."
From planning to writing, titles, and promotional text.
You can have Claude help with almost every step of bookmaking.
Therefore, even one person can release many books.
What used to take months has become overwhelmingly fast.
[Important] However, "Total AI Outsourcing" will get you BANNED
There is something I absolutely must tell you here.
If you thought, "Then I'll just have Claude write a ton of books and win by releasing 100 of them,"
That is dangerous.
In 2026, if you do that, your entire account will be deleted.
Amazon has strengthened measures against low-quality, mass-produced AI books.
・If you use AI, you are required to declare "AI usage" at the time of publication.
・Thin, mass-produced books are rejected during quality screening.
・If you violate the terms, your account will be suspended.
The low-quality mass production strategy called "churn and burn" is a complete landmine in 2026.
So, what do you do?
The answer is simple.
Have the AI do the draft, and then add "human value" to it.
Your own experiences, unique perspectives, and truly helpful specific examples.
Only books where a human has added these will be evaluated and continue to sell.
AI is a tool that makes work 10 times faster.
But "what to convey" is decided by the human.
This is the same thing I always say.
Basic Steps to Earn Royalties
Let's organize the flow.
Step 1: Choose a profitable genre
This is 90% of it.
Aim for a genre that has demand and where the rivals aren't too strong.
Go "narrow and deep" rather than "wide and shallow."
Step 2: Create the book with Claude (Human finishes it)
Proceed with planning, structure, and writing using Claude, then add your own perspective and experience to finish it.
Step 3: Create a proper cover
This is often neglected, but it's extremely important.
On Kindle, whether someone clicks is determined by the first impression of the cover.
Cheap-looking covers are avoided for that reason alone.
Step 4: Publish and increase the number of books
It's not over after one book.
Increase it to a second, third, and so on.
This is the only way to grow your income.
[The Real Goal] Actually, "Reader Lists" are more profitable than royalties
Now, this is what I really want to convey.
To be honest, it's a waste to aim only for royalties.
The true value of Kindle publishing lies elsewhere.
It is being able to collect a "reader list."
Let me explain what I mean.
Someone who bought your book and read it to the end.
That person is your fan and a high-quality lead.
But Amazon does not give you the buyer's contact information.
So, you do this:
Prepare a "free bonus" inside the book and place a lead to your LINE or newsletter, saying "Click here if you want to receive it."
Then, what happens?
The dedicated fans who read the book will register for your LINE or newsletter one after another.
In other words, you use Kindle as an "entrance for customer acquisition."
And here is the main point.
You introduce affiliate products or your own products to the collected reader list.
Kindle royalties might be a few hundred yen per book.
But what if you could introduce products worth thousands or tens of thousands of yen to the readers gathered through that book?
The scale of earnings changes completely.
In fact, overseas, the standard way to earn has become "collecting an email list with free e-books and selling products there is the most profitable."
While receiving royalties from Kindle, you also gather dedicated fans.
You deliver affiliates and products to those fans.
This two-stage approach is the true optimal solution for Kindle strategy.
Don't "sell books," but "gather people with books."
If you can have this mindset, the digits will change.
Points of Caution
Finally, things I want you to follow.
① Declare AI usage correctly
Follow Amazon's rules and properly declare AI usage.
Hiding it will be a violation of the terms.
② Do not do low-quality mass production
As I said earlier, mass-producing thin books is a cause for account suspension.
Please create something valuable, one book at a time.
③ Follow rules for affiliates and leads
There are rules for external leads and introductions within the book, such as PR notation.
Be sure to check the terms of Amazon and each service.
④ Don't give up immediately
It's normal for Kindle publishing to take 6 months to a year before you can earn.
Moreover, royalties are paid about 60 days later.
Don't rush; the person who stacks up the number of books wins.
Summary
To summarize:
- Using Claude makes bookmaking from planning to writing lightning fast.
- The royalty rate for e-books is 70%. One book becomes a "small vending machine."
- Income is determined by "number of books" rather than talent. Stacking works.
- However, mass production by outsourcing everything to AI will get you banned in 2026. Add human value.
- And the real goal is the "reader list" rather than royalties. Gather people with books and connect them to affiliates/products.
Even people who thought "writing a book is impossible for me" can no longer use that excuse if they have Claude.
What's important isn't talent.
It's the content: "Whose problem are you solving with the book you release?"
Start by deciding on one theme you can talk about.
That is the entrance to everything.
Finally: Sharing the "Backside" of Earning
Thank you for reading this far.
There are things I intentionally didn't write in this article.
・Specifically, what genres of books are easy to sell?
・How to create a lead flow to move people from the book to LINE or newsletters?
・How to deliver affiliates and products to the gathered readers?
These "cores" are shared within the open chat "X Operation Strategy Room."
It's a place to talk frankly about know-how for earning with AI.
Furthermore, I am currently developing a "tool" to accelerate distribution, and once it's completed, I will provide advance guidance in this open chat.
Participation is free.
If you are someone who wants to "build a system to earn while sleeping with AI," please take a look.
▼ Open Chat "X Operation Strategy Room"
Let's ride the new wave faster than anyone else together.
I look forward to your participation.
Ryuji Yamamoto (@ryuji_affiliate
This article was reconstructed and explained based on overseas articles and various public information. Amounts are estimates calculated at 150 yen per dollar. The earnings introduced are specific examples, and results vary by individual. There is no guarantee that the same method will produce the same results.
