"I am Bhaal. I love murder. I call murder good. So, if you don't murder, you are evil. You call me evil. I call you evil. Let's fight. See who wins. All my followers are good if they murder."
Hmmm. Are Bhaal and his followers good or evil?
I say neither. They're just misunderstood. Maybe you can be a good follower of Bhaal. Maybe you could just murder only bad guys. But then... Who is truly bad? What IS good and evil? Is anyone ever REALLY innocent? Hmmm? Maybe I call the tieflings in the Grove evil, like Kagha.
It's all based on your personal perspective. Right?