Whats wrong with Evil?

There has to be Light & Dark, there has to be Up & Down, so there has to be Good & Evil. I'm not saying that I don't love to bask in the sunlight of good and spiritually uplifting thoughts and prayers but sometimes I need to fall back to the dark side (and not just because they have cookies) I find my mind in situations where dark thoughts are a comfort to me and playing out scenarios in my head keep me from acting on impulses that should not be acted upon. Now don't get me wrong I'm not saying that I'm a serial killer or going to blow something up, I just think things to myself about myself that usually involves no one else. I don't bow and pledge to the dark side of myself but I do tend to visit there from time to time, like going to Vegas for the weekend. I mean come on there is light and dark Rye even.