The problem is you can't draw non-arbitrary lines. Consider an example I ran into a few years back. It was a web project, lots and lots of closeups of female

The problem is you can't draw non-arbitrary lines. Consider an example I ran into a few years back. It was a web project, lots and lots of closeups of female genitals. Porn? No--educational, the purpose was to provide as wide as possible a sampling of what's normal so people don't get focused on the idealized representations in porn. One of the sports companies did something similar with breasts, it was accepted.