The Terrible Truth Behind Batman's Greatest Villain
It is always the butler.
I'd prefer sebastian. He's better in every way and literally can't betray you, he's invincible, attractive, he can make lots of delicious sugary food and he is a badass demon.
Badassery is his specialty, but in all honesty, I'd prefer a modified Accuracy International Arctic Warfare .50CAL with an extended 5km scope. Lot's more effective