I'm becoming more comfortable with nudity and I was hoping to start selling NSFW art through commissions in the future, but my friend brought up the point that minors could be buying it and I would never know. The scenario I'm worried about is what if their parents find out and I end up getting in trouble? I'm less worried about being charged back if that were to happen as it couldn't be helped, but I'm worried about guardians wanting to possibly get me in trouble. Would the minor lying about their age work against me in the way of "ignorance of the law is no excuse," or is there something I can do to protect myself against that possibly happening, and ways to protect myself if it does happen?
I see plenty of other artists who sell NSFW art and have never seen this issue happen, so I wasn't aware that it is a possiblity until my friend brought it up.
For reference I live in California if it matters due to any laws that anyone might know of. Please and thank you?