I kinda wonder, does the hourglass age her with the rate at which it turns back time? Or does it take thr time that was set back and multiply it in some way? Most of the time it turns only back a few seconds so it seems more likely it's multiplying it.
@Wulfleyn someone has stated already earlier but the hourglass doesn't age her. She's growing more cause of the amount of time she sleeps now due to using the hourglass. Think of it as a forced growth spurt.
@ichigodream The Hourglass accelerates her aging whenever she uses it.
With that said, she died in her twenties and a year passed since her reincarnation, so she now actually looks her real age. Soyeah, she IS as old as she looks.
But of course, people in this timeline can't know that so to them Aria is a 15-years old jalbait.