It would still be incest (just because it is another personality does not mean they are not brother and sister), so I guess the question is then is Akira/Mirai LIs or not?
The technically no incest was to a comment I made on itch.io, but with how little the dev wants to give away it's impossible to know what he means. After the recent story revelations which I mentioned in a previous post that mentions Yagami family members having silver hair and red eyes I assumed Akira is not our blood sister, I did wonder if that was some kind of link to what he meant, but who really knows.
I'm almost positive that you're correct that Nobume has to be all in on the Ren path whilst Luna, Diana & Artemis are Inei, tough to gauge by the small interaction but was it Sayori (the one who was head researcher) would probably be Inei as well, the only other two that we've met so far are Maeda & Mei I think and I've no idea what path they would be on, that's assuming they are actually all LI's.
Game seems to be pretty ambiguous as to the direction they will head regarding Akira & Mirai (contrast to character like Nobume, "who has that "Why are you acting like this, now he hates me now" line, as well as Ren and Nobu younger selves flashback scene, which solidifies her as Ren's LI)
You're right. The MC (Inei) even questions it saying only one of the sisters have red eyes (Mirai, but not Akira), none of them have grey hair. So it could be the case that Akira is the adoptive sister.
But I thought for the Zone's (this site's) definition of incest tag, incest basically includes "not just blood, but also step sibling, but also adoptive siblings as well."
So I dunno. Kinda feels like it's going on the muddy waters as to boundaries of these characters.
And it kinda also feels like the dev is in a lose-lose situation here. If the relationship between MC (whether Ren or Inei) and Akira/Mirai becomes LI relationship, some will have problem saying "it's incest" whereas if they are just left to be brother and sister relationship (and doesn't take it further), then there will also be folks mad saying "Why are you dangling these pretty girls in front of me and not letting me romance them."
As the saying goes in the Witcher, seems like dev will have to choose "the Lesser Evil" lol.
Yeah, I agree Sayori seems to fit more with Inei (given she wants to use MC as her guinea pig, only viable option looks like Inei, otherwise Ren would be dead in her first guinea pig experiment lol).
Mei, while it is possible to be on either one, I'm leaning slightly on Inei path. Her first interaction with MC was as his Inei personality, and I think Inei's "bullying Honda" aspect is a big positive with Mei in terms of their banter.
Maeda, she could go either way.
From the looks of it, since the game started off with Inei's personality, a lot of LIs seems to be heavily stacked for Inei's path (with exception of Nobume) and there's just not as many LIs stacked for Ren (ones like Akira and Mirai, if they become LIs they'll likely be crossing over to that incest territory).
I mean not that it really matters since I do prefer Inei (over Ren), but if dev's objective was to diversify/branch out more with different MC persona (i.e. Ren), I'm not sure it's that much of a success (though I could be wrong).