Hi, I'm playing the linux version on steam deck right now, but for some reason I can't select the "No one" route, the way Charlotte and Frederique's routes can't be selected. All the other routes work fine. Has the linux version been updated yet?
If you are looking for the loveless route, you will find it under Guillaume's route.
After clicking on his portrait, at the prompt 'who did King Auguste want to become queen?' click on 'Me'. And then choose the last option, "No, I behaved as instructed and King Auguste chose me".
This will get you onto the Loveless route. I hope this helps ^_^