I just thought of this, but if you're right, maybe Lapis goes evil because she learns that her "sister" wasn't really her sister at all but some other person possessing her sister's body. (It would explain why Evil Lapis calls her a "thing.")
That's exactly what I was getting at, yeah. It would make a very good (albeit cliche) "reason" for her to go off her rocker, especially if Lapisis (my nickname for her little sister for now) decides to attempt to trigger the revolution route through unsavory means in the "original" storyline.
I don't think it would be cliche, really. If anything, despite the sheer amount of isekai stories where the protagonist takes over the body of a fictional/fantasy person, they almost never have to face that person's friends/family being upset that their loved one's body is essentially being puppeteered by a stranger. (The only exception I can think of offhand is Ascendance of a Bookworm, and it gets resolved quickly.)
It's pretty common in KR isekai I think, there's a newish webnovel whose entire premise is predicated on a family member getting asspained that his younger brother got possessed
(Also, reincarnators are more common than possessors, and typically don't face any issues from the original inhabitants due to having lived through infancy in the world, while Myne is a possessor which is relatively less common.)
last edited at Sep 1, 2022 5:54PM