Simple, play it through YNOproject.

https://ynoproject.net/oneshot/
Don't worry, they got permission from the developers.

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So, now that you're in, you may think that the game is bugged. Don't panic, just select the blank space and press Z.


Or you can move the cursor to exit before pressing Z, this will allow you to play the game in Japanese.

There are some things that you need to account for. Firstly...

This is the 2014 version.
Exiting the game early will lead to tragic consequences.
Additionally, the 2014 version is generally considered to be inferior to the 2016 version. This is because the 2014 version lacks the Solstice route/ending and generally has less content compared to the 2016 version. (although the 2014 interface sounds are better in my opinion.)

You can move with wasd instead of the arrow keys, this applies to all games in YNOproject.

You can play it on mobile as well.

At one point, you will need to enter in a 6-digit code, it is the release date of the 2014 version in mm/dd/yy format. Solution: 063014

If you have a YNOproject account, you can earn badges while playing this version of OneShot.

Here is a list of badges that you can earn: