Responses

Exactly! He looks like 14 or 15. Maybe the artist decided that the balance wasn't right so he made Arthur 14 here compared to the novel. Actually it's much better if he's 14 here than 12... Imagine him flirting and fighting to death while still a kid.... Too OP in my opinion and the balance doesn't seem right(〜 ̄△ ̄)〜
As far as i know... He's only 12?! They should have made him atleast 15 or 14!!!! HIS BODY DOESN'T MATCH HIS AGE AT ALL!!! AND HE'S ALREADY FLIRTING AT THAT AGE!!!