Guy Woodhouse

Guy Woodhouse is one of the main antagonists of the horror film Rosemary's Baby and for much of the movie seems to be the loving partner of Rosemary who aids her through what appears to be a psychotic episode during her unexpected pregnacy.

However in reality Guy is revealed as one of the higher-ups in a Satanic conspiracy and a man who willing sold his own child to Satan in order to obtain wealth and power, as part of this pact he also had Rosemary mother the Antichrist (in the form of the titular "Rosemary's Baby").