Can you be both nice and evil?

I was doing some reflection and noticed that over the years since childhood I have been called evil. It seems I am two extremes. I am either really nice or evil; actually, I think I am both. I mean, I can be mean.. everyone can be mean. But I am only mean when I am angry like most people. But I was thinking, is it possible to be both evil and nice? Is that called "pure" and "evil"? I have a morbid sense of humor and I am very sarcastic, but I would never physically hurt someone :] children and animals are attracted to me, but in a good way. So I cannot honestly be a bad person. I think my personality maybe too dark for some people. So is it possible? I have had people tell me before that they hate me because I have a morbid personality, etc. For instance, my mother says that I remind her of Juno and maybe like Wednesday Addams.