Buffy The Vampire Slayer S01E08

I, Robot... You, Jane

 Willow meets a boy on the Internet, but "Malcolm" is really Moloch, an ancient demon released from bondage after Willow scanned his "book" into the school's computer. With help from Ms. Calendar, Sunnydale High's computer teacher, Buffy foils Moloch's plan to upload himself into a giant robot.