Draco's use of the knife had been inspired by his Aunt Bellatrix, whose lessons (particularly in Occlumency) had been a large part of what had gotten him this far. Not that he had publicly credited her for it, but he thought most people probably assumed as much, since Draco's rise to power had correlated with his father's fall from grace. If anyone actually thought about it, of course.
He put the knife away now, though. He had drawn the first blood, but there were subtler tortures than that; subtler than the unforgivables too, which would never be Draco's favorites, though he knew many of his fellow Death Eaters preferred them. After a moment of thought, he flicked his wand and heard the satisfying crack of breaking bone in the man's wrist, which would cause enormous amounts of pain with the way he was hanging.
"So," he said. "Do you think the attack at the apothecary was the same sort of attacks we've been having lately? Violence against people that Death Eaters care about?"