It's a Book, Not Scrap Paper

There is a "book" in this world, a magical artifact that can turn anything written in it into reality.

Fifteen-year-old Dazai obtained a "book," but it was only a copy.

He couldn't write anything in it. He could only use it to learn about other parallel worlds.

That was enough.

Dazai didn't care who had the original. He only wanted to use the information he obtained to do everything he could to save his friends.

The "book" he held always remained blank, silently supplying him with information.

Then, one day, words appeared on the page for the first time:

0.75x-3=2.1

0.75x=2.4

x=,

x=,

x=3!

Dazai, who had watched the entire calculation: ...

Ah, it's wrong.

*

Chen Jianhe, 13, sixth grade.

Her grand ambition is to get into the best middle school in her district, then work her way into the best university. After that, she'll find the best job, get promoted and earn a raise, become CEO, marry a handsome rich man, and reach the pinnacle of life.

During PE, she just found a treasure on the school field: a book whose writing disappears on its own.

It's the perfect scratch pad, and she can probably use it all the way through college.

Chen Jianhe is delighted and uses it to work through a math quiz with gusto.

Then, after class, the teacher calls her into the office and asks how she got "2.1+3=2.4," and whether she has invented a new mathematical law.

Chen Jianhe has no answer, so she decides to study harder.

Her specific plans for studying harder are to do math problems in the "book," pass notes with classmates, play Gomoku, and draw little dogs.

*

Dazai, who looks at the "book" every day, realizes something is wrong.

Getting the math problems wrong is one thing, but why is she drawing dogs, too? Is she doing this to spite him?

*Primarily a Bungo Stray Dogs crossover, spanning a long period of time

*Set in an alternate universe, with no connection to any real organizations, groups, or people

*Screenshots taken on August 19, 2025

Theme: With hard work, anything is possible