They aren't photos though and if they are age of consent or over aren't they not minors then? I know in Europe, they graduate high school at 16 and are legally able to drink beer and wine. Doesn't sound like a minor to me.
I feel this shouldn't be needed to be explained, because you're using "legally drinking beer" as a measurement of adulthood, which is baffling. But anyway...
You are confusing "
age of consent" (the ability to engage in sexual relations without legal repercussions) and "
age of majority", which is the age at which you legally become an adult.
Let's take my country, Spain, for example. Age of consent here is 16 years old, while age of majority is 18. You can't smoke, drink, drive or vote until you are 18. Now, the age of consent being 13 doesn't mean that a 34-year-old can have sex with a 16-year-old kid. That's not how it works. There is a series of requirements, including closeness in age between the two people, so that a relationship is protected under the age of consent.
Anyone below the age of 18 is considered a minor, period. It doesn't matter that 13 is the age of consent: if you have sexual photographs of a minor, you are in possession of child pornography. That's how it is in the vast majority of countries.
Oh, and depiction of underage people for sexual purposes still falls under "child pornography" in most countries. So the excuse of "they aren't real" doesn't fly at all.