Damien Darkblood is a minor character that originated from the awesome Invincible series.
Damien is a demon from Hell, who went to Earth and became a private detective. He often investigates cases that somehow have superheroes involved.
In Invinicible, he was investigating who murdered the Guardians of the Globe (a Justice League stand-in). However, when he reports his findings, he is mocked because Omni-Man already confessed to killing the Guardians of the Globe.
In Astounding Wolf-Man, Chlope Hampton hired Darkblood to find Zechariah (a vampire and the former mentor of his father).
Damien is based on Rorschach. He has a similar attitude and appearance (espically in his trench coat suit). He uses "Hurm" as an interjection like Rorschach.