Draco Antares was an Emperial Knight under Roan Fel's Empire. During his career he fell in love with Fel's daughter and when she was rescued defied his Emperoro and went to rescue her.
Draco was captured and forced to reveal the location of the hidden Jedi Temple. He returned to Fel believing to have dishonoured the Emperor but Fel forgave him.
When Fel tried to unleash a Sith made toxin on Coruscant to kill Krayt Draco engaged him in a duel to stop him falling to the Dark Side. Draco slew the Emperor, saving Corscant and eventually marrying the Princess.