The Lady in Blue by Fred M. White

Clutton contemplated the writhing Magavitch much as if the latter had been some quaint specimen on a microscopic slide under the searching analysis of the scientist. He could see the twitching of the thick lips and the oily ooze on the yellow skin. He knew this man inside and out, knew that he was playing on his nerves as if they were so many fiddle-strings, and gradually reducing him to a condition of absolute fear. This was the sort of thing he liked, this was some reward for all that he had given up, and to his mind the subjugation of the wild animal made amends for many past sacrifices and disappointments.

"You flatter me," he said. "But what would your associates say if they could hear your praise of Spencer Clutton? And what would they think of it? What are you thinking about yourself?"