I'm at a loss at trying to turn on NSFW Mode.
Edit: After looking at the replies to my comment and some help, for anyone still confused on how to turn NSFW On by default, if you bought the game, go into your "My Library" and download the latest version of the game there. That will help you have NSFW turned on by default if you wish for it. If you wish to turn NSFW off, go into the game's settings and scroll down to turn the setting off.