Because it's both hidden by default even on Mac and windows pc
Here is a link where you can find it
You can find your save files in:
users\your username\appdata\roaming\strive\saves
And i would recommend you to download the bugfix:
https://itch.io/t/1167355/bugfix-for-10d-v6b
Put it in the mods folder like this:
users\your username\appadata\roaming\strive\mods\Strive-1.0d-Bugfix-V6b
Start up your game-> Click on mods-> Click on the bugfix.-> Apply-> Exit the game-> and restart your game
Here if you still cant download it. https://www.mediafire.com/file/mh0j0w47pfijt6y/Strive-1.0d-Bugfix-V6b.zip/file
Male/futa futa/futa also works. And it will be left to the mods. But i dont think anyone will make one.
There exist a workaround for it. You just need to change 1 thing in the save file.
https://jsoneditoronline.org/# go to this site. Put the save file there. Then go to characters/search for your char hid/statlist/statlist (you see it right i put it there 2 times)/agreed_to_marry (check this) after that save the save file to disk put it back to the save folder delete .json and you should be able to marry the character you wanted.
If thats not working for you. Then you can edit it manually where they are. Either by using Notepad++ or editing it here: https://jsoneditoronline.org/# (remove the .json when you put it back in the save folder.)
The save files are simple json files.