I'm gonna be honest with you... It is very easy for minors to view nsfw content online. The real responsibility lies in the parental lock programming and the NSFW tag should be enough for the parental lock to pick up and exclude access. Personally I am just happy that i dont have children and when i do i will be very happy if i dont have a girl. Thanks to the easy access of online porn these days young people are growing up much more sexual and there is only so much you can do. There is no possible way to put a parental lock on every device that your child could potentially have access to. This would include public and school computers as well as all the ones at home, handheld gaming devices as well as consoles both at your home at video arcades and at the homes of your child's friends. Not to mention their smartphones as well as their friend's. Sounds like an almost impossible feat to achieve.