Are you aware Majority of Age is not a black or white situation? In most western countries, Majority of age is actually at 21. At 18 you can do almost everything, you are partially an adult. And for some people sex is only ok at that age, but in my country you are legally a consent given person at 16. As well as for other stuff like voting on an election, or getting your first drivers license, all at 16.
But, if I wanted to marry or have a legal entity registered to my name I'd need to be 21. You are not a child when you are 17 and 364 and neither you are a full fledged adult at 18 and 1 days.
I don't know if the discussion is still linked to the story about adoption/legal custody/Marc etc. - as I had promised, I kept myself away from this thread for a bit.
But if this is not about that stuff, I can chip in, I would agree that it is not a black or white situation, though also due again to language (e.g. consent, adulthood, majority, full rights, independence).
It's not by chance that most contracts in English start by defining a bunch of words
.
E.g. I know a country where age of majority is 18, age of consent is 14 (and statutory rape was eliminated a number of years ago), to vote for the higher chamber of the parliament you must be at lest 25 years old, and if I remember correctly to become President at least 50.
But if you look at the map I attach, most countries of the World indicated 18 as age of majority meant as legal adulthood (in reality, I know in the past in USA one could volunteer for the military at 17 even if the parents were against, which means for that specific case, could have been said the age of majority was actually 17) - I admit it comes from Wikipedia, may not be the most reliable source, but if we take it for good (they use "legal adulthood", but even what that means, can change), it means actually the majority of the World uses 18 (green).
To reconfirm the "different ages for different things", since we are in forum about an erotic game, can look at the second picture, for the age of consent for heterosexual situations (dark blue is 16, lighter shades of blue lower age, yellow 12, other colours, older than 16), though of course even there, there can be various other things which can influence (e.g. age distance, roles, cannot anyway be filmed or photographed), and the source is the same.