>>712781552She clearly doesn't look 5 though.
She looks like a teenager, and the game says shes 19. Which fits.
Also, even in real life there is a grey zone with age.
There are many 21 year old girls / boys who could pass as 17. So if you ignore what the writer actually says, any young character can be feasibly called underage, even when they are not supposed to be.
If the character can reasonably pass as the age stated, thats what people should go with, rather than making up head canon that she's actually younger.
The only reason normalfags think the character is a kid is due to the big anime eyes, which don't exist in real life.