As much as he was learning he liked the power he had to walk freely and intimidate here, Rodolphus did not like the restriction on his actions. The only thing keeping Munch from being in the excruciation pain of a Crucio right now were the others around, watching, milling about, working. Bella wouldn't have hesitated, but Rodolphus had a bit more restraint now that he had a focus for his devotion.
"Munch, aren't you?" The way he said it, there was an obvious threat implied even in the simple question. "And is this a part of your job?"