I'm giving this a VERY early 5 stars, simply based on this games potential. Since it's basically only a demo/proof of concept, the actual quality of the game going forward can deviate significantly in quality from the demo.
So why the early 5-stars? Because this 5-minute demo had more atmosphere and intrigue than most visual novels manage to establish in 10 hours. The lighting, settings and especially the eerie soundtrack creates this really dark, grimy and almost chilling atmosphere that is just really engaging. The demo sets up a very interesting premise around what appears to be a main charater with actual depth.
Speaking of the main character, she looks great, especially nude! There's a certain element of "realistic girl next door" to her, which I like. Huge bonus points for actual animated scenes instead of just still-photos, which again adds to both the games atmosphere and the MCs overall feel and personality.
I beg the developer to give this game the time and effort it so thoroughly deserves, because with the right amount off care and attention, this thing has the potential to be GREAT.
Good luck, dev!