-Was a rich and quite possibly schizophrenic British girl who was to become a nun.
-Born with what is called in the Buffy World as "the sight" meaning she can see visions of the future--she even saw herself being turned into a vampire by Angel, who was also her lover.
-Pointed out to Angel by Darla as she was walking the streets with her 2 sisters.
-Became Angel's victim as he tortured and killed all her relatives and friends, which drove her insane as people already called her crazy (including her father) since she had "the sight", blamed herself for what happened to everyone she loved.
-Was changed into a vampire by Angel/Angelus upon about to enter a convent.
-Sired another Brit named William, who became to be known as Spike and became his lover for centuries.
-Came to Sunnydale with Spike to have a magical ritual performed on her to bring back the strength she lost during some attack back in Prague several decades before.
-Killed the vampire slayer, Kendra who was called after Buffy had died in Season 1, by hypnotiznig her and then slashing her throat with her nails.
-Called forth the demon The Judge as a special birthday present for Buffy.
-Her and Spike left Sunnydale following Angel's failed attempt to take over the world.
-Drusilla left Spike for a chaos demon, but then returned to Sunnydale only to find Spike in love with Buffy.
-She then disappeared from the series for a while and from then forth, only Spike returned to Sunnydale while Drusilla was sometimes featured on the spin-off Angel.
-She is led to LA by the demonic and hell-spawn lawfirm Wolfram and Hart to re-vamp and sire Darla, who was brought back as a human after Angel killed her in Buffy Season 1 and who was basically her "grandmother" in the vampire familiy (Darla-Angel-Drusilla-Spike).
-Her and Darla go on a killing spree in LA and even kill boss of Wolfram and Hart, Holland, his employees, and his wife and friends.
-Was almost burned to death by Angel when he attacked her and Darla.
-Has never appeared on Angel since, but appears to still be living as she was never killed on Buffy or Angel.
Darla-staked by Angel, brought back as human by Wolfram and Hart, killed and re-sired by Drusilla, stakes herself to save her baby
Angel-stab in the heart with a mystical sword by Buffy
Spike-sacrificed himself by wearing a mystical amulet that "only a true champion could wear" to kill all the vampires escaping the HellMouth