I’ve just reread the story, and I have an account to comment now, but there is just so much to this story, it’s hard to get all into words.
First of all, I consider Aya to be a very admirable person. She already went through so much and had to grow up so fast even before she blipped out of existence for seven years. And that blip not only ruined her life, it disconnected her from her last remaining relationships. Yet, the moment she found her footing, she took off running to try and get her life together so she can stand as equals with Koto and Erika again.
I think a lot of readers have been underestimating her because of her literal age. The number itself doesn’t tell you nearly as much about a person as many might think. It doesn’t reflect maturity, wisdom or life experiences. Ironically, in recent chapters, Aya has been the one acting the most mature compared to Koto and Erika. I think she‘s been doing just fine on a personal level but the other two are going to make things much harder on her before they get better, especially Erika.
So let’s address that elephant, all the clues, all the hints, they point directly to Erika as the one responsible for Aya’s disappearance and reappearance. Some deniers will claim to the bitter end that there is no definitive proof, but the only reason why it hasn’t been fully revealed yet is because we are building up to that confrontation.here are just a few missing pieces that need to fall into place.
1) The Kumagaya siblings’ story. First, the brother is in eerily similar circumstances regarding his education, then the sister implies she suspects Aya‘s real age and asked her a very specific question. Learning about their story would give Aya some idea of what happened to her.
2) Erika‘s hidden feelings. In a previous chapter, Aya mentions she likes Erika for her bluntness and because she has “no hidden side”. Unfortunately, that’s far from true, Erika keeps a lot of her deepest emotions bottled up and hidden away. First her unrequited crush on Koto, then her growing resentment and jealousy towards Aya. There are a different ways they could be revealed and I think it will be soon.
3) Aya’s repressed memories. Erika was the last person to see Aya before she was spirited away and it doesn’t seem like the kind of conversation she told anyone about and it seems she prefers that Aya not remember. If it was as bad as I think it is, I can understand why Aya‘s mind might suppress. Like I said, she was comfortable around Erika because she believed she had no hidden side, but then as she allowed herself to get closer to one friend, the other turned on her. It must have been quite the shock and a betrayal of trust. And since these were evidently Aya‘s last moments, it will probably be the final piece.