Finally managed to find the time and play the demo. It was a very enjoyable and unique experience - I've never seen a game where you play as a character such as Rei. I especially enjoy the fact that while he's a cold blooded killer when trying to discover the Doctor's methods, in his everyday life he's such a grouch and can actually be pretty funny too. It's a nice contrast. I'm also pleasantly surprised by Minami - I don't usually like characters like him, but he really has a charm I didn't expect to see!
The demo was pretty short so I'm not able yet to make a really detailed review, though I must mention something that really bothered me. In the settings, you have the "Censorship" option - but I have no clue if a yes means "Yes, apply the censorship" or if it means "Yes, the gore/sex will appear", or if you'd rather have the opposite, then I don't know if a no means "No, don't apply censorship" or "No, don't show the gore/sex". It's really confusing as I don't know if I have to check or uncheck it to actually get to see the mature content, and even when I was trying both things during the slighly gorey CG, I didn't see any difference so I guess it wasn't hardcore enough to apply for this...