So everyone's curious about the "child" thing🤔
Welp remember in the previous chapters the archduke mentioning "she's probably 15 at most" so yes, he views bea as someone 'young'
Also, heidi and trigger, when desbcribing her looks, mentions that she look like a 'girl' or a 'boy'. They use a korean word that means a 'young female' or a 'young male'
As well as other characters, like the knight Evan and Chris, and even the tailor in the ch34 views her as a 'child' not a 'woman'.
Welp hope that clarifies things😊