That would be Ron Perlman in a lot of makeup.
As a “good demon,” Hellboy may be a walking oxymoron, but he’s the singular exception to the rule. The first Hellboy movie establishes the occult world as a distinctly unfriendly place; the title character aside, demons are creatures of pure evil, existing only to destroy and consume. Moreover, those who battle them use crosses, crucifixes, rosaries and other recognizable emblems of Christian faith.
More about the tradition of ugly heroes in this review from Christianity Today. Yes ... Christianity Today.