olderthannetfic:

Ah. You’re still thinking about that tag in a more cultural sense, but that’s not what it’s for. If you dig through the FAQs and such, the explanation is in there somewhere, but to summarize, it refers to:

On page depictions of sexual activity including at least one character under 18.

(So if they just kiss or you just say she had sex but you don’t show intercourse, oral, etc. on the actual page, it doesn’t count.)

AO3’s underage tag is actually to protect users who live in jurisdictions where <18 sexytimes are banned from art or banned unless there’s ~artistic merit~ or whatever. Around the time AO3 was starting up was when Australia was having a big upheaval over such things, so it was on people’s minds in the Anglosphere.

Whether the sex is problematique or age gap or whatever doesn’t matter. The actual age of consent or laws around sex in the real world location these characters are in, if any, does not matter. Your 17-year-old UK characters fucking still need the warning or CNTW even though that’s laughable in context. 18 tends to be the age most used in international law for… like… porn star ages and such, so 18 is what AO3 went with. Never mind that it’s not necessarily the age of majority or that age of consent laws can depend on partner age, etc. etc.

Unlike noncon/graphic violence/character death, this warning isn’t there primarily because readers find the topic squicky.

It’s a legal ass-covering thing.