Disclaimer: JKR owns Harry Potter's arse and John Constantine has Vertigo (or is it the other way round?).

RaIsInG hElL aT hOgWaRtS

A Hellblazer/Harry Potter Crossover

Chapter 6:

Harry and Professor Constantine walked the Hogwarts grounds in silence. When they reached a spot a few yards from the whomping willow, Constantine stopped to light a cigarette. After a few long drags, he looked at Harry and smiled.

"Whadaya know? Snape isn't such a pillock after all!"

Harry stared at Constantine. "What do you mean?"

"Snape was the one that figured out how to stop you from keeling over every time we looked at each other."

"How?"

Constantine stared at his cigarette for a moment. "I had to give you some of my blood Harry."

Harry suddenly had an urge to run away. "What's so special about your blood?"

John raised an eyebrow and grinned. "On its own, nothing. Common as crap. But a few years back, a total wanker of a demon gave me some of his. We think that old snake-face has some of the same blood as well."

"Snake...?" It took a moment for Harry to catch on. "Oh, Voldemort!"

"Yeah." Constantine took a last drag of his cigarette and crushed it under his heel. "Now pay attention kid, 'coz if you don't, the shit's really gonna hit the fan. There's going to be side effects. The nightmares, you've already experienced. But it gets worse. Your going to have urges, you've got to control them."

"Urges?"

"Do I have to spell it out to you? Fine, you'll want to shag just about anything in a skirt."

Harry started to laugh. "I'm going to be a total perv because of your blood?"

John wasn't laughing. He wasn't even smiling anymore. "No, you ungrateful little shite, because of the demon's blood. Its name is Nergal. It feeds on perversion and chaos. This gets worse, by the way."

"There's more?"

"Yeah." John lit another cigarette. "This is where things are going to get really weird. You know how sometimes you make things happen because you're pissed off or scared?"

Harry nodded. "There was one time when I blew my aunt up because she was putting down my mum and dad."

John grinned. "Well, now, if that happened, she'd be splattered over the landscape instead of bouncing around your back garden. If you cast a spell when you angry or scared or suchlike, it'll increase the magnitude of the spell. Like when you tried to use the cruciatus on that cow Lestrange last year-"

"You know about that?" Harry interrupted.

John shot him an annoyed look. "Yeah."

"She deserved worse."

"No arguments there kid. Sirius was a good mate." Constantine held up a hand to prevent Harry from interrupting again. "But that isn't the point. If you tried that on her now, the way you feel, you wouldn't just hurt her. You'd shred her nervous system and maybe even a few poor sods who were dumb enough to be standing next to her."

"Are you that powerful?"

"I'm not really a wizard, don't even own a wand. But I know enough about magic to keep pricks like Lucius Malfoy good and scared. Now, like I said, you're going to have to learn to control all this. So I'm going to be giving you some extra training outside of class."

"When?"

"Soon. I have to hash out a few more bits with Dumbledore first."

The bell rang in the school.

John looked at his watch. "That'll be dinner, c'mon."

As Harry sat down next to Ron and Hermione, something Professor Constantine said hit him like a brick wall:

"Sirius was a good mate."