Demona

Demona is the main antagonist in the TV series Gargoyles and was a recurring enemy of the clan, having a deep hatred of humanity many of her plans revolved around the extermination of the human race so that Gargoyles could live in peace (or simply to appease her thirst for vengeance). It is also noted that Demona hates humans as a way of dealing with the intense guilt she feels at having been a part of the events that led to the massacre of her clan. Like for example her betrayal of the humans her clan guarded by night ultimately led to the slaughter of nearly all of them both gargoyle and human. Also her actions are directly responsible for creating gargoyle killing hunters which drive her race close to extinction. Plus for the next thousand years she ultimately double crosses every group she comes into contact with always ending up alone.