itch.io

It already is.

You can download bundles for the offline version from here:

https://spnati.net/bundles/download-bundles.html

Follow the instructions on that page to download and set up the offline version. This will allow you to download the entire game and all its files; note that this is a several-GB download thanks to all the character sprites!

Extract all the files, and you'll have offline SPNatI. Opening config.xml in the main folder (use Notepad) will allow you to change some settings, such as enabling debug mode and unlocking all endings. Open index.html in your browser to play the game

Copying from FAQ:

Unfortunately, SPNatI is hardcoded to link sex and gender, and has been since its earliest versions, since no one knew it'd get this big. This means that years of content, and hundreds of characters, are now written and structured with this link in mind and would require substantial revision. You're free to suggest solutions, but people have tried to no avail.

Can I download the game?

You can download bundles for the offline version from here:

https://spnati.net/bundles/download-bundles.html

Follow the instructions on that page to download and set up the offline version. This will allow you to download the entire game and all its files; note that this is a several-GB download thanks to all the character sprites!

Extract all the files, and you'll have offline SPNatI. Opening config.xml in the main folder (use Notepad) will allow you to change some settings, such as enabling debug mode and unlocking all endings. Open index.html in your browser to play the game!