You roughly demand to know why he had to kill your poor swet sister, tears stinging your eyes as you yell at him. He answers, "She figured out how I keep getting away scott-free." He's got a smug smirk you don't like tugging at the corners of his mouth.
"What d'you mean?" to ask.
"She found out," he says, "that I don't work alone."
You hear the click of a revolver being cocked behind you and start to turn, but you're not fast enough to see the face of your killer.