You also have to consider that the Adulthood age in Italy it's 18 and not 20 or 21 like in Japan (tell me if I'm wrong but it should be like this)
The minimum legal age of consent in Japan is 13 years old, however most of the prefectures have it as an unwritten rule that you need to be between 16-18 and above for consent, and the legal age now dropped from 20 to 18, but you still can't drink alcohol and stuff until you are 20, however you can have an apartment and bank account on your name.
Ah, okay, now I understand better, I tried to search on Internet by I didn't understand what age was the right one; but anyway in Italy the age of consent is 14 (also in Italy you have to be at least 16 for real consent, even if it's not stated by law), you can start to work at 16 and at 18 you're legaly an adult: you can drink alchool, you can vote, you can have an apartment, and also can study for having the car license (but you can have a license for smaller engines since 14, like some types of motorcycles, depending on their power).
But anyway, by this I wanted to confirm your previous comment, so the story with Noel, their relationship, is totally legal, in Italy and in Japan ヾ(❀╹◡╹)ﾉ~
Your welcome
Noel's age is 20, it's written in volume 2 chapter 5 page 6. He is legal everyone~