i do also feel that the original idea was that she was going to be slightly underage, the whole insistance that she is actually 18 gives that feeling sometimes, like all those games were no really she isnt my mother she is my "landlady" (unless you install the incest patch you degenerates), but what do i know to be honest it could just be going for the whole "im an adult but everyone still treats me like a child just because i like to have fun" feelI think she is very young and likely underage but okay from the game.
She can grow further to be voluptuous like her mother. (I think Verena is a vegetarian from a long time, even before has Rick and Arianna)
Women can become thicker by simply pregnant and giving birth. (And the more child they have, the more thicker they possibly be)
but again even if she is an adult petite women do exist and it doesnt have anything to do with them being malnourished or them "growing up to be voluptuos later on" there are plenty of women in the world who are just small and thin and... they remain small and thin for their whole lives even after multiple pregnancies or whatever, its just their complexion and i feel like arianna is supposed to be that way, she is not a big girl like tia or even like just like frisha
also is rick considered thin? seriously? i compare his model in game with the MC model and they arent all that different, rick has quite a thick upper torso in some ways thicker than the MC and broad shoulders