It's like two mask you can't pick one. It's harder to stay mature if you have a child like figure running around
I figured it was a way to show how weird it was for her, since her brain wouldn't have physically grown and developed the necessary brain bits for adult thought, and she's trying to force it through due to her adult soul. But when she's not actively working on it, the kid body overrides her Japanese consciousness.
It’s explained more in the novel but as it’s a big deal, NO SPOILER FO’ YOU SIR
Am I the only one who kinda hates her inconsistent maturity? She keeps on changing between acting like her physical age and acting like her mental age. Just choose one plz (〜￣△￣)〜