DISCLAIMER: I don't own Buffy the Vampire Slayer or Devil May Cry.

Buffy, Xander and Willow danced in the Bronze, Xander having dragged the girls away from their schoolwork. As they danced, a British voice said to someone nearby, "Where's the phone? I need to call 911. There's some big guy out there trying to bite someone!"
Buffy rushed outside, where she found a vampire trying to feed off a girl. Buffy dragged the vampire off the girl, and started hitting him. Xander ran inside, going through Buffy's purse to find a stake. After pulling out a napkin and fumbling with a tampon, he found a stake. He ran outside, tossing Buffy the stake. The vampire called out, "Spike! Give me a hand!" Buffy staked the vampire, and it turned to dust. Out of the shadows, a man in a black leather coat, with bleached white hair, stepped into the open, clapping. "Nice work, love." His voice and British accent gave him away as being the one who had said the vampire was outside.
"Who are you?" Asked Buffy, seeming uneasy.
"You'll find out on Saturday."
"What happens on Saturday?"
"I kill you."

Giles went through his books. "Here we are. Spike. He's known as William the Bloody. Earned his nickname by torturing his victims with railroad spikes. Well here's some good news. He's barely two hundred. He's not even as old as Angel. Oh…"
Xander leaned forward. "Good oh or bad oh?"
Giles looked up. "I think your idea of running away might have been a good one. Spike has fought two slayers in the last century, and he's killed them both."

Giles picked up the phone in his office. He had to double check the number, but he got through easily. A deep male voice answered. "Devil May Cry."

The window to the school parent teacher night burst open, and dozens of vampires poured inside, Spike standing at the front. "What can I say? I couldn't wait."
Spike started to enter the school, but a man in a red coat, with white hair, who ironically bore something of a resemblance to Spike, stepped into Spike's path, and with an easy movement, launched the vampire straight back out the window. Buffy and the others watched as the man raised a sword, and decimated the other vampires. The man looked out the window, but Spike had already vanished. Buffy charged over to the man in the red coat, snatching a pencil off a table as an improvised weapon. "Alright, who the hell are you?"
Giles stepped up next to Buffy. "Buffy, wait. He's on our side. Buffy, this is Dante. He hunts demons."

Buffy, Willow and Xander walked in their respective groups, each leading a group of children who were trick-or-treating. As Willow's group reached a door, they were all changed into demons, their costumes becoming reality. Willow, who was dressed as a ghost, fell to the ground, before stepping out of her body. She ran over to Xander, who had been dressed as a soldier, and now was a soldier, shooting at the monsters with a machine gun. She called out to him, but he pointed the gun at her. "I suggest we get to safety, mam. It's dangerous out here."
Xander, we can't. We have to find Buffy."
Buffy walked up to a tree, leaning on it. She was dressed as a seventeen hundreds noblewoman. Xander and Willow went up to her, when Xander turned and saw a demon. "We may have a situation."
Willow knew who to turn to. "Buffy, what do we do?"
To her horror, Buffy fainted.

The three returned to Buffy's house, locking the doors. Cordelia walked in close behind. Willow left Xander in charge, walking through the wall.

Giles was looking through a book, with Dante sitting in the library, his feet on the table. Suddenly, Willow appeared out of the wall. Giles jumped, but Dante wasn't bothered in the least.
"Giles. We need your help."

Giles and Willow were looking through books, while Dante was still in the same position, his feet across the table. "So everyone became their costumes?"
"Yes. Xander was a soldier, Buffy was a seventeenth century noblewoman."
"And you?"
"I'm a ghost."
"The ghost of what, exactly?"
Willow uncomfortably folded her arms over the outfit she had worn under the ghost suit. Her arms covered her stomach, and she leaned lower as if trying to vanish. "Well this is nothing. You should've seen Cordelia. A leotard with cat things."
"She became an actual feline?"
"No. She didn't change. She was the same old Cordelia, but in a cat costume. Wait. She got her costume from Party Town. Everyone who changed got theirs from the new place, Ethan's."
"Ethan?" Said Dante, standing up. "The owner of this shop, was he a scrawny British guy with a gravelly voice?"
Willow nodded, and Giles and Dante exchanged a glance. Giles headed out the door. "I'll deal with him. You two go and help the others."

Xander punched the pirate onto the ground. Angel came and got him. "It's strange. Beating up that pirate gave me a weird sense of closure."
The group headed to a warehouse when they saw Spike appear around the corner, leading a group of demons. Willow went inside with the rest, but Dante stayed outside. The demons reached him, and were instantly sent flying. Finally, only Spike remained. Spike was uncertain, stepping back. Finally, Spike charged, meeting Dante's fist head on. Suddenly, the children were reverted to themselves. Dante was distracted by the children, and Spike had vanished when he turned around.