I just finished the demo and here are my thoughts:
Backgrounds: I guess it was okay. It's just that the backgrounds is too strong prolly adjust the luminance of the photo? Though I think it is the style of the backgrounds, it was fairly okay for mi. It just that I find it too hard to look at, prolly my preference in VN's.
Sounds/Music: I guess the music is what I like best in this demo. The sound effects are on point and they give a good feel to each scenario.
Art/Sprites: I guess they were okay considering this is indie. I can appreciate it. I think the proportion of the sprites are good. You prolly draw people better than me.
GUI: It's quite an old school type of interface. It reminds me of those flash games back 2012. Though since this is already 2017, I 'm really bothered with the lack of "auto-play" button, never mind the "skip", or the "backread", I am more concerned with the auto since most of the times, I just prefer reading the game thoroughly than bother clicking all through out. I guess that's my only complaint.
Story: I am wondering what is the story is all about. Is it about the cafe? Or the city? Or the characters? The demo just introduce the characters, but not the mc. Not their purpose or what the mc's motive or something. The synopsis told me about the White Ash, and that the people are magical and that they are science-oriented something. It somehow confuses me. Though I have no problems with the dialogue so far, it is pretty neat for an indie. If not for the minor typos, lack of punctuation, and the words are going out of the text box (prolly you could fix that later as you release the full version). The story is still vague for me, I was hoping to understand the thought of the overall game with the first chapter but it didn't showcase the idea. Prolly that is what the demo lacks. Probably, this is just a suggestion though, you should've add that "impeding fate awaits them" teaser in this demo to excite the players for the cliffhanger rather than asking them if they want an "Easter Egg"... which is supposed to be a surprise but nvm.
Finally, I was surprised with the sandwiched author's note. :'))))) It would have been better if you put it in the beginning or at the end rather than in the middle. Or prolly you are part of the game idk and that is part of the story.
The overall demo is okay. I am looking forward to the full version of the game and improvements of the actual release in the future. Good luck.