It might be worth trying on the idea that you don't exist.
At least not in the way you might imagine. Consider where your consciousness goes when you fall asleep and aren't dreaming. Or when you're put under for surgery. I don't know if you've been put under, but for me one moment they were putting the mask over my face, and the next moment I awoke and the surgery was finished. I didn't experience any passage of time. You could say I wasn't here or didn't exist during that period.
It seems like certain things have to be occurring in the brain to say that you are awake, conscious and here. So this consciousness has certain dependencies, now what are they? Can we deactivate certain parts of your brain and you still feel here? I think so, but if we take away enough, you're no longer here. And I think if we add them back, your experience becomes more vivid and here, like slowly coming to in the morning, or when a deaf person has a hearing implant added so they can hear again.
So having the feeling of being here is a higher order thought, depending on the hardware faculties to be functioning. And that hardware can be substituted for non-biological equipment and you can be conscious of the readings of the sensor. It also comes in degrees, meaning we can be more or less here.
Which is to say, maybe the NPC doesn't have to be biological. It just needs to have the same dependencies to exist that exist now for you. You couldn't be reading this in your sleep, you read it when all the dependencies exist to say, "hmmm, that's interesting but my left frontal lobe says..."
PS. I hear you have nothing further to add, but my own left frontal lobe was compelled to chat. Apologies if it disturbed you, have a good one.