Related Clues:

• Haunted house occupants, it's said
• Pac-Man's enemies
• They say "boo" but not "yay"
• Séance invitees
• Such keys perhaps best left in cupboards?
• Sir's tip (anag.)
• CBS sitcom set in a haunted mansion
• They might be summoned during a seance
• Good innkeepers producing spirits
• Strong drinks? Removes clothes drinking one up