Tiefling

Half-Demon/Daemon/Devil race in the D&D games, first introduced with 2nd edition's Planescape, where they had hints of demonic nature (teeth, little horns, a tail maybe). In 4e, they are depicted with ramlike horns, large tails, and a dark red skin tone.

One of the recurring themes of Tieflings is that others find them inherently unsettling. This has survived into 4e, in which they get a bonus to CHA to represent their mad intimidation skillz.