He's a robot with a human mind and subconscious, being a scientist and the head of the UAC.
Dr. Samuel Hayden is arrogant, narcissistic. He is also prideful, stubborn, and dedicated to the study of demons as well as science in general. He is willing to do unethical things for his research and studies, having a dislike of anything he can't control.

He only has a blue LED on his face that he sees through, having no other facial features, and emotes only through lights flashing or dimming.