This brings to mind a question I have been bouncing around in my head.
Who will be the first main girl to have sex with the MC outside of Eternum?
I think it might be Luna, not 100% sure why I think it'll be her, but that's just the vibe I get.
I very heavily doubt it will be luna. I think she will be one of the last girls to go anywhere lewd. She was basically unable to really touch people for most of her life and It very clearly had a lot of impact on her. There's no way she's going to be dtf anytime soon.
I think the most likely one right now is Annie. They have the date lined up and while she says she wants to take it slow, I think it's clear that the reason for that is not discomfort on her part. She wants to take it slow because she thinks that that is the way to get a proper relationship with the mc going. She's holding on to the idea of a fairytale romance so she wants to keep things slow, but I don't think it would take much for her to change her mind on that. If she gets the feeling in the moment that she has to make a move, she will make a move, as we have seen in her scene in 0.2.
Nancy will keep things to Eternum for a while in my opinion, since the fact that it happens in Eternum is the excuse she currently uses to justify it to herself.
Other than that I think the most likely after Annie would be penny.