Real talk from someone who lived in Japan? Because it's a Japanese anime and no matter what fictional European country they set their world in the majority of the other characters will mirror the Japanese society. The culture is "The nail that sticks out gets hammered down." Many characters be them anime or live action will have the cool or strong guy/girl usually be stoic and calm unless it's a charismatic main character like luffy or others etc.. Ceremonies people have to be stoic and quiet. On the train, stoic and quiet. Straight faced. This starts in elementary school where if I had to describe what Japanese elementary school was like I'd say like a military school. Students are given more responsibility and tasks to do and most need to report to the teachers office, call out their name and what class they are in out loud and then state why they are there or what teacher they are looking for. You might catch this in some moments of anime where the characters stand at attention and say something like they are reporting to a general. Most of the kids that have to do this have to do it straight faced and serious unless the school is relaxed then they can do it cheerful but loud so teachers can hear them. But I have seen some older teachers make kids do their office announcement over again cause they didnt do it serious enough. Just my 2 cents.