The demon army kept coming and the four were backed into a corner, losing. Illyria turned to Angel as she decapitated a demon.
"I do not wish to die like this, halfbreed. I have an idea, but it carries great risk."
"More than dying?"
"Much more. But he owes me. Ph'nglui mglw'nafh, Cthulhu R'lyeh wgah'nagl fhtagn! Iä! Iä! CTHULHU FHTAGN!"
California shook as a creature of mountainous size broke through the asphalt, scattering buildings and demons every which way. No mind could fully comprehend his horrific appearance. His scaly body was unfathomably huge, with wings that seemed to shred the rainclouds while his talons scratched at the groaning earth, and somewhere up there was an enormous head with a face full of teeth and writhing tentacles. The demons were like ants to him; within seconds, the entire block was a blood-soaked wasteland.
Cthulhu turned towards the gang, who felt very tiny. The Great Old One's voice crackled with immeasurable age and malice, turning Gunn's hair as white as Spike's.
"THERE. WE ARE EVEN, ILLYRIA. NOW QUIT STALKING ME."
Then he strode off terrifyingly. The others stared at Illyria, who shrugged.
"We used to date. He cheated on me with Shub-Niggurath."
Author's Note: Cthulhu and Shub-Niggurath were invented by HP Lovecraft and are, I'm told, in the public domain. The others, you know the drill, Joss owns all etc.