Weevil

The Weevils are a humanoid alien race, who come through the Cardiff rift from their homeworld. Not much more is known about them, not even what they call themselves, except that they are vicious and don't communicate very well (which is why nobody knows what they call themselves).

Physiology
Weevils are roughly human in shape and size, but are a bit taller, and have odd faces with many sharp, fang-like teeth.

Due to their overall outward physical similarity with Humans, many Humans mistake them for other Humans at first, and when they see the face and teeth they assume the Weevil is a Human wearing a very realistic mask.

Behaviour
Weevils seem to be vicious creatures (as seen when one attacks a man who walks up to it), and apparently do not communicate, or if they do, only with grunts and roars.

Source

 * TW: Everything Changes