But the notion that a five-year-old is able to consent to anything is absurd. So we have to draw the line somewhere. The UK has chosen to draw the line at 18, which for some kids will be absurd, yes. But for others it will be appropriate. And yet others will still not be emotionally mature at 18 and capable of making that kind of decision properly.
>>gambit+Ox
Not just the UK. In about 30 of the United States of America the age of consent is 16 [1]. Beyond that marriage is permitted with a note from parents of the minor and approval from a judge up to 1 or 2 years below the AoC depending on the state.