The Invisible Line

While lunching with a friend yesterday, we got to talking about the no-no's in a series, and whether there truly are any no-no's at all. The resulting conversation was fascinating and I've found myself revisiting it time and time again since I got home.

Now I'm curious how all of you would answer the same questions…

Is it ever okay to kill off a regular character in a series?

Would an author's decision to do that, prevent you from reading future books in that series?

~Elizabeth