Suspension of disbelief suspension of disbelief suspension of disbelief 🥹🥹🥹so... they reported her reappearence to the authorities and they decided to do absolutely nothing at all about this whole thing, yes?
Tbh, girls do slow down growing at around Aya's age and many women in their early 20s (Erika and Koto seem to be 21) don't look drastically different than how they did in their middle-late teens. For example, even in the manga, there isn't a huge height difference between them. It's a more realistic explanation than anything supernatural for anyone else like Erika's dad who did meet Aya.The authorities and Eirika’s dad were way too chill with Aya’s situation. Normally you would expect them to react to a girl that went missing 7 years ago suddenly reappearing without aging a single day more seriously