Age of consent is such a murky thing. Why is the hard line 18 (or 16)? "Romeo and Juliet" laws help (so that an 18-year-old with a 17-year-old partner doesn't get criminally charged), but I think there need to be more nuanced rules. I subscribe to the half-your-age-plus-seven metric, personally, but legal bodies don't like there to be nuance and complexity in laws, leading to those horrific "legal countdowns" for famous teens (paparazzi laying on the ground outside of Emma Watson's birthday party trying to get upskirt shots the second she became 'legal' comes to mind) and all those "barely legal" porn categories.