Heres some of my favorite Buffy and Angel ,Vampires and Demons

 The Master

The most powerful of all vampires is the Master. Trapped in a sort of dimensional prison, he was unable to enter our world, only able to act through his minions. With the help of these vampire followers, he was able to cross over to our world briefly by luring Buffy to his lair and biting her. Fortunately, Buffy wasn't dead and surprised the Master, impaling him. His minions, led by the Annointed One, tried to resurrect him using human sacrifice, but were foiled by Buffy, who then smashed the Master's bones to bits.

Spike -William the Bloody

Nicknamed as "Spike" because of his fondness for torturing his victims with railroad spikes, William the Bloody once hunted side-by-side with Angel. Since then, Angel had a change of heart about killing humans. Spike on the other hand, will kill anyone who gets in his way. The Annointed One found  Spike became angry and hoisted him up into the sunlight, burning him .

Drusilla

After killing her entire family and visiting every conceivable mental torture on the young Drusilla, Angel turned her into a demon on the day she took the convent's holy vows. Completely insane, she rampaged through Europe, slaughtering victims mercilessly until she was almost killed herself by an angry crowd in Prague. Spike saved her and has been working to restore her to her full power.  

Darla

Darla was killed by Buffy...Darla was Angel's sire together they rampaged through Europe .Until Angel was killed a young Gypsy girl and was given soul

The vampire that gave birth to Conner....
Darla  sacrificed  herself  to give birth to Conner....
Darla brought back as a human by Wolfram and Hart  to be told that shes diring ........Angel and Darla made love...So Wolfram and Hart got Druilla  to sire her  but that backfired on them when Darla and Dru killed most of them  leaving just two alive Lindsey and Lilah..Darla  and Dru left LA when Angel trid to burn them....When she came back to LA she was pregnant with Angels baby....

Harmony Kendall
Harmony Kendall was ostensibly Cordelia's best friend
throughout high school . Harmony was the archetypal
bimbo: blonde, pretty, empty-headed, and only caring
about her appearance and her dating status.
All this changed however, come graduation day. In
order to stop the Mayor from devouring the entire
class of 1999, the Scooby Gang enlisted the help of
most of their fellow pupils, including Harmony.Where
Harmony was made a vampire..

Angel the vampire was "born" in 1753, making him 246 or
247 in vamp years (these are the dates given on Angel's
tombstone in flashbacks of the Angel episode "The
Prodigal"). Angel was a bit of a rogue, and a drinker as
well. He was, in fact, out drinking one night when he
encountered Darla, who turned him into a vampire. In
1860, he met Drusilla, killed her family, drove her mad,
and then turned her into a vampire. In 1898, he killed
the daughter of a Romany (Gypsy) tribe, and the tribe
cursed him by restoring his soul ,He lost it again when Buffy

made love to him ....but Willow manage to restore hes soul

The Judge
 The Judge is a blue skinned black eyed humanoid with a crown of  horns on his head.
 ''It's a legend, way before my time, of a demon brought forth to rid the Earth of the plague of humanity, separate the righteous from the wicked and to burn the righteous down.'' The Judge could sense humanity in those near him and burn them with his touch. He proved impossible to kill, and had to be broken down into pieces and imprisoned in boxes.

Kinderstod Demons
Description: A humanoid with long curving teeth and long white hair. It's eves are able to extend of stalks to drain it's victims.
Powers: Kinderstod demons can become invisibe to those who were not ill. They feed on the life force of sick children by sitting on top of them and draining them with his eye-tenticles. The children then looked like they died of their illness.

 Eyghon

An ancient demon who lives by possessing the souls of dead or unconscious people, Eyghon comes to Sunnydale looking for its next victim. It seems that Giles if familiar with the demon, as is his friend Ethan. Back in college, they summoned the demon using an ancient ritual. Ethan and Giles both bore the mark of Eyghon-a-tattoo-on their forearm.To save himself  Ethan tattoo Buffy  with the mark Eyghon

Order of Teraka

A secret society of demonic assassins. Once called upon to eliminate a target, they will not stop until they have completed their task.

The Mayor
He Asended to become a demon

The Gentlemen
Voice Stealing Fairy Tale Monsters.

Adam
Part Demon/Part Human/Part Machine
All Killer

D'Hoffryn - Able to transport moartals to Arashmaharr the world where demons are made.

Glory / Glorificus - not really demons but she did fight against Buffy so . . . A Hellgod fast strong and evil.

Rusell .....A rich Vampire who feed off young women ..He paid Wolfram and Hart , to keep his killing a secret., Angel killed him by pushing him out of a window at Wolfram and Hart........

Marcus.... A Vampire with a liking for torture .Spike hired Marcus to torture Angel  to find out where the ring of Amarra is..The ring makes a Vampire unkillable ......

Dr. Roland Meltzer  who could deattach  part of his body and reattach them again ...He stialking a young woman he had one date with ..He was destroyed by Angel....

Penn ....... Sired by Angel  ..he used Angelus techniques to kill  his victims ...he was killed by Kate Lockley....

Boone an old demon rival of Angel from Juarez . He was hired by Wolfram & Hart to kill Angel ..He help Angel to unmask the dirty-doing of W&H ..he was killed by Angel

Doug Sanders the leader of the Pyramid cult ... Harmony tried to give the cult Angel by betraying  Angel and the gang .... Doug was beheaded by Angel

Silas ..Crimson robed head priest of the Covenant of the Trombli...He ruled Pylea where humans were  called cows and were treated like slaves ,,He was beheaded by Cordy ......

Fez-toting Moroccan brain demon... He was hired by Lilah to terrorize Cordy by giving false visions that were painful ...Angel killed him .he threw re-bar through his brain........