Considering how the game is a "do whatever you want" kind of game, it'd be hard to make a demo that doesn't just let everyone have access to all of the content but the story from the start.
Well from what I gathered there's 3 different concepts going on:
-There's the normal explore the town and H-Event search. Different outfits and stats allow you to trigger different H-Events.
-Normal Dougion exploration and battles. The Combat system he's shown off the most takes place here, with mid-battle rape and H-Attacks.
-The 'Rouge-like' dougions and battles. He called this the 'dream state', and apparently the objective in these is to primarly put together an outfit combo and escape. Battles are vastly simplified here, and if you succeed at making an outfit combo you get an H-Event.
From what the demo he's suggesting, it'll at more have a starting H-Event or two for the intro, and then the Normal exploration for general battles. So expect this to have far less playable then all of the stuff he's been showing off as he's apparently cut all of that out for this 2/14 release and later plans to add more towards it after feedback.