Incubus

Incubus (plural incubi) was a demon species.

Physiology
Incubi appear human and maintain their appearance over decades. When they employ their hypnotic powers their eyes turn solid black flecked in white. Their blood is colored blue.

Powers and Abilities
Incubi feed on life energy through intimate contact and have an "hypnotic" effect on people, allowing the incubus to influence the actions of their targets.