Okay, gave it a play because your visual style caught my eye. First things first, said style is done nicely, I liked the aesthetics and the medieval presentation. That said, I personally think the game would benefit from a more fitting font typeface for the actual story - the current one is very at odds with the rest of the medieval imagery. I understand you don't want to pick something ineligible, but given that the style is such a key thing I really feel it would benefit from something more in keeping.
Secondly, as this is a text story the text really has to be on point; in the very first paragraph there is a sentence that doesn't make any sense, and I noticed a few more grammar and spelling issues throughout. As this is essentially the entirety of the game there really is little room for error. I did notice that Russian language was an option in the menus, so if English isn't your first language that is fair enough, though I believe there are plenty of ways to have a native speaker proofread your script. Also, a game like this really needs some audio, even just some public domain medieval/fantasy songs.
I understand this is a demo, and perhaps these features will be worked into the full release, this is just my thoughts on the game in its current state.