As an artist

I don't even do anything remotely related to kids in my tf/tg art, unlike my peers who do AR and AP stuff. The questionable legality of it being misinterpreted scares me to death. But as a general question do we need to set a line in the stone for what is not okay? When does a tf cross that line absolutely? We have several episodes that graze the line and some old ones even cross but do we need to write it down? This certainly blew up after a week of quiet though.