Dream Demon
The last few days in Maybrook, people have been dying at random. Police and Coroners have not found why these people are dying. Willow, now working at a the nearby hospital as a tech has gotten hold of the medical examinations of the dead people and found that the brain cells were fried as if they had the energy sucked out. She felt the presence of some paranormal energy and took a small scraping of the brain matter and stuck it in a tube and hid it in her pocket. After work she came back home and studied the cells. Meanwhile, more people were dying. Kaitlyn and Faith patrolled nightly and found nothing different than vampires. Willow finds traces of paranormal energy that matches the energies of a demon that lives by feeding off the human mental energy generated by dreaming.
Willow, "This demon feeds off REM sleep generated energy. When you dream the demon basically eats the dreams but this kills your brain in the process."
Kate asks, "How do we kill it."
Xander, "We'll have to go to sleep and hope it attacks?"
Giles, "Actually, that's not a bad idea. We can go to one of the victims homes and let Xander go to sleep."
Xander, "Hey, no, no, no, I'm sick of being everyone's butt monkey, remember?"
Willow, "I'll perform a spell that when it feeds, it'll solidify so you can fight it."
That night, they go to a recent victim's home and Willow does the spell. Xander goes to sleep. They all wait outside. Using Kaitlyn's paranormal investigation equipment, they have Xander on video camera. The demon suddenly appears and solidifies. Kaitlyn and Faith run in and fight it.
Xander, "God dammit, that is the last time I'll be bait. Stupid demon ruined my dream."
Suddenly someone jumps in through a window and tackles the demon. The attacker snaps the demon's neck and rips it's head off. The demon dies.
Laughing, the attacker turns around, "Heard I'd find you here."
The man de-vamps.
Kaitlyn pulls the wooden bullet gun, yelling, "Vampire!"
Faith stops her and asks, "Spike?"
Giles, "Oh hell, what do you want?"
Spike, "Lookin' for a new place to stay at... I like this town. Plenty of demons to rip apart."