Disclaimer: Fanfiction, not mine.
It was a dark and stormy night at Hogwarts, on All Hallow's Eve. Potion's Master Severus Snape paced about in his dark office mixing vials of poisons and powders into a boiling caldron. He held his wand above as to keep the concoction self stirred, while chanting from an old and crumbling book.
"itch-bay, obble-cay, ailbate-jay"
There was a knock on the door which caused him to drop his wand into the mixture and he growled with annoyance. "Yes, come in.... This better be good you've just ruined my lunch..."
The door slowly creaked open, letting in a draft which blew out the candles that lit the room. The only light came from the occasional bursts of lighting beyond the window.
"Mr. Snape?" Crackled the dark figure in the doorway.
"Yes you imbecile, that is my name. Now tell me why you've disturbed me."
"Sorry." Lightening flashed revealing the mystery guest to be Albus Dumbledoor, "Please excuse my voice..." He grumbled in the raspy voice, "you'll see I've gotten myself a bit of a cold." This was of coursed followed by a small coughing fit.
"Ah, Headmaster, well would you be interested in joining me for lunch, I was preparing some soup. A secret family recipe."
"As wonderful as that sounds Severus I'm only stopping by to give you your mail. You've, ahem, got an interesting message from... well I'm not sure, but it certainly is interesting." He handed over the letter.
Snape thanked him and snatched it up, relighting the candles with his wand, "It would seem I've been invited to a party..."
"A party?" Croaked Dumbledor, "Doesn't that require you to have friends?"