There is violence, esp as involves the killing of the zombies (dubbed the Unconsecrated). These are zombies that infect, however. They don't eat flesh. Which I think makes them more tasteful to read. I wouldn't go so far as to say Mary is a bad role model, but I definitely didn't think she was a positive one, either. She is more obsessed with her life-long dream of "finding the ocean" and doesn't seem to really care about her friends. It's a fun, interesting read, however. (Somewhat of a cliff-hanger at the end which is not resolved in its companion novel.)