Lucius wasn't even pretending to himself that he had any other motive than the obvious. He would of course strive to be civil, but if the Muggle Studies professor was half as delicious as he looked in his picture, Lucius would be hard pressed--literally--to keep his hands off. Nevertheless, he could still act every inch the gentleman when circumstances called for it. For instance, Professor Hygge might not be willing, and Lucius, for all his proclivities, never engaged in rape. It was just no fun.
Lucius arrived at the door and tapped politely, wincing at the Muggle Studies sign. He could ignore that. He could.