Born with a mean heart, your villain is a cruel sadist who enjoys toying with your fears and emotions. This is someone who will make you think you're going to get out of this okay just before dropping the other foot.
My one cousin. I actually wrote a poem about him once. The kid was my rival, and a total jerk at times (when we were kids). He remains, the exact opposite of me. An extroverted, sensor, who's thinking, and perceiving.