Yes, and one with unrestricted internet access. Can you elaborate on how someone underage would abuse this system? They can’t buy one at the store, can’t reuse one that has expired so finding one won’t help, and if theft is a concern they would just need to be secured like any other restricted good. I would say it’s at least as secure alcohol, tobacco, or firearms.

You know how there are stores that sell restricted substances and verify your age by checking a provided ID? Have those same stores sell a cheap, sealed card with a confirmation code on it. You can enter that code online to verify any service. The code expires after a set period of time after it’s first use to prevent sharing and misuse.

This system would be as secure as the restrictions on the restricted substance, such as alcohol, so it should be fine for “protecting the children”

The opening scene involves the two of them locked in an apartment slowly starving to death while their neighbor attempts to summon a demon and dies leaving behind piles of edible meat.