Buffy and Spike meet Edward and Bella:

Buffy: OMMFGWTMFF! A vampire! I must stake his ass!

Edward: No! Not the hair!

Buffy and Edward fight whilst the following takes place.

Spike: Ooh! A human. Yummy.

Bella: ummm… Edward?

Buffy: (stakes Edward)

Edward: (poofs into a cloud of dust)

Spike: om nom nom.

Bella: (dies, because Spike just went on nom nom on her blooooooood)

Spike: LOFL!