Tempus (? - May 17, 2001), also known as the Devil's Sorcerer, was a powerful demon who possessed the power to reset time and create Time Loops using his hourglass. At some point, this evil sorcerer came to be in the service of the Half-Faced Source of All Evil, and well-insulated himself so that none but his master and other very powerful dark forces could contact him.
In 1999, the Source sent Tempus to assist a demon styling himself as "Inspector Rodriguez", as he was investigating why so many demons had been vanquished that year, including the Queen of the Underworld, Hecate, and claimed to have found the Charmed Ones. Tempus told him to get all three of the sisters into the Halliwell Manor by midnight, but, when he did, he was vanquished, despite killing Phoebe. However, the time-manipulator had managed to succesfully create a Time Loop, causing the day to repeat itself over and over by use of an unknown potion and his own hourglass. The second time Rodriguez tried to kill the witches, he failed again, killing Phoebe and Piper but failing to kill Prudence. On the third day, the sisters learnt of Tempus' interference and, after capturing and vanquishing Rodriguez, used a spell to break the Time Loop and defeat Tempus, leaving him to retreat to the Underworld, defeated. About two years later, he was contacted by the Source, who asked him to reset time due to exposure of the magical world, though the act of turning back time again would destroy him. Regardless, he obeyed his master and was vanquished forever.
Much later, five years after his destruction, a Possessor Demon planned to bring back one of the most powerful demons in history. One of her minions, named Tam, asked her who she was bringing back and thought of Tempus as a possibility, which confirmed his demise. However, it was actually the Half-Faced Source she was reviving.