I was raised with a strong sense of fiction vs. reality. All of the "movie magic" of makeup and special effects was shown to me when I was young, so blood and monsters were completely demystified to me. That said, I still didn't consume "violent" media until I was 10-12-13. In that range. The logic was that I should enjoy stuff that was age appropriate because I would cease to enjoy that stuff when I got older; I had the rest of my life to enjoy "mature" material.