if we aren’t getting a forced ending there’s no way this isn’t going to crash and burn. no boundaries set between two people who are in dire need of boundaries between eachother. demisexuality or sexuality is moot - no matter how you cut this it was an immensely immature decision on their part and they are trying to desperately grasp at a solution between eachother while halfheartedly acknowledging things won’t be the same but there’s no genuine desire to form a new relationship. this being said relationships IRL are messy but messy relationships crash and burn HARD before it actually gets better. buckle up i guess.
I could see an angle for it not being forced and still have it work out.
Eri's never once initiated intimacy or felt attraction of her own volition, but she's responded to the feelings and actions of those she's dated in the past, and seemed to have "bought in" over time. Whether she felt anything beyond what she might assume is expected of her, remains unclear, though I suspect that is the case.
But Fuyuki has always been different for her; and I think that is significant enough that they could go the distance.
And if the author does have Fuyuki & Eri navigate the future successfully, it could be off the back of the sheer depth of their connection, rather than the incongruent nature of their respective "definitions of love" they have for the other.
Eri asked Fuyuki to keep loving her and looking at her, because she knows that's how she's developed feelings and attachments in the past. And the fact that she already treasures Fuyuki, means that she's now "with" the person she holds dearest, and that adds an additional layer of focus and meaning to this relationship they're figuring out.
It might mean that Fuyuki has to be the one to initiate intimacy, but she'll never have to share Eri again with anyone else, in any context. And, Eri's not immutable; people do change over time, and she was operating from the stance of ignorance and naivety before - that's not the case now, and with awareness can come understanding.
It certainly won't be easy, but I fully believe that they care enough about one another to make the effort, and over time I could see them figuring out the optimal way for them, even with the inevitable bumps in the road.
I would fully accept a well-written ending that sees their relationship failing, as well. The author's clearly shown that they possess the skill to make that work, and make it a good ending, if not a "happy" one. This has been fantastic thus far, and I don't see myself being mad at the end, whatever the conclusion, just on the basis of the quality of art and writing.
But, I do think the groundwork is there for Eri and Fuyuki to beat the odds.