I haven't played through all of the content yet, but this might just be my favorite game I've come across here so far(and I've played all of the designated popular ones from that section). It's not necessarily because of the lewd content, which I personally don't prefer to other games, but because of the basic logic of the game and the environment itself, which I find very poetic, interesting and generally jibing with my vibes about what's a good story space. I really applaud you for that, and I'm sorry if I'm not more coherent in my congratulation, but I'm sure I'd offer some awards to this game in certain departments compared to the other erotic ones like it, if I had the chance to. That's just to say, I really think it far surpasses other games in certain ways, that I find highly valuable. So, really, thank you for that. The idea is great, and don't pay attention to those who say you stole it without merit. Whatever the inspiration for it, it's clearly very different in a lot of ways from the game it's similar to story-wise, and insofar as the similarities stop at the older male/younger female relationship and codependency in a survival-like deserted environment, and the names of the female character and that of the game, I'm not even sure where such an argument gets its meat to begin with.
This is truly an awesome game, and you are a wonderful developer, especially if we are to observe the indended directions you have in mind for the future development of the game, as well as how you apparently wish to listen closely to our feedback. The proof of concept is spectacular and I'm honestly enjoying just going back and forth in this tiny world you've created at present. I think you can make something extremely exciting with this, and I can't wait to see what it is. But if I were you, I'd retain the mysterious tone as much as possible, and limit the number of protagonists to the two currently available, at least for now. That way, you know for sure you'll protect the magic it currently has.
EDIT: Just a small caveat, my only complain with this game is the Ellie art. I think it's bad, but that's just me, and perhaps some people like it. But the art of everything else is spectacular. So thumbs up for that, and perhaps rethink Ellie a little - as a suggestion from me.
EDIT2: Is there any penalty for annoying Ellie(are there any internal stats that track her mood towards us) by saying the wrong thing or anything like that? I'm mainly asking in order to know if I can experiment without having to save.