I ended up doing a lot of research on how to reset the game because i had a problem with the achievement unlocks, part due to having played the game offline once, most of the routes would not unlock achievements for me anymore.
I found little to no real info on how to do it. But after i actually did it, the least i can do is share it.

Hope it helps.

1 - Uninstall you game from steam, you don't want your steamcloud pulling whatever magic tricks it can use to get your saved files (if any) onto your computer again.

2 - Go to your steam games file, where all your steam games are installed, and find your "Negligee" game folder (not your actual negligee, that would be silly).

Should be something like: "\steamapps\common\Negligee"

Delete the whole folder.

3 - Go to your windows user folder.

Something like "C:\Users\<insert badass username here>\AppData\Roaming\renpy\Negligee"

Also delete that folder. (The Negligee one, that is)

4 - Reinstall you game on steam. If everything whent right, you should now have a clean install of the game, like it was the first time you played it.

Thank you for reading. Have a nice day.