|Morgan Wayne: Every woman wants him,|
every man wants to kill him.
"He bent and touched his lips to her forehead, cooling now and glowing with the indefinable pallor of death. And as he did so he swore an oath that was not formed in words, but etched in acid on his soul. An oath that her killer would die by his hands, and soon. Derr's identity was his secret. It would remain his secret. Let the police discover her body in the natural course of events. Long before they could possibly get on the right trail, Morgan Wayne swore to himself she would be avenged."
The Avenger (1952) - Matthew Blood
Seems that Matthew Blood was a pen name for Ryerson Johnson and David Dresser - more famous as Brett Halliday. A sequel (Death is a Lovely Dame) also appeared a couple of years later.