Harry potter : Darkness from the inside

The Blood Lust of The Pure

The bushes shook to Luna' s despair.
"Harry? This isn't funny!" She squeaked. A familiar green glow filled the air as strong arms wrapped themselves around her from behind. She was being hugged.

"Why are you so scared of me,doe?"
"I'm not scared of you but you have to admit this place is eeire at night." She huffed.

For a moment they stayed position then Harry turned her around and they kissed. It didn't last longer one he had already convinced her he had meant no harm. At the right time he moved down to her neck caressing it for a moment. Luna was lost in the pleasure of the moment, her senses were cut off so she didn't realize Harry's mouth widen giving way for his fangs.
He bit down releasing venomn into her neck. Her scream brought full alert to the two men of their whereabouts.

"DAMN!" Sirius said pounding his fist into to nearest tree trunk. "We are too late."
Remus sniffed into the air. "No she still alive. Lets go!"

'Now let's get this over with we still have other things to collect' His counterpart hissed.'Do as I've shown you. We can't complete our mission if you don't do this.'
Harry drew his hand back and plunged into Luna's chest. The poor girl began to convulse violently. In one swift motion the heart of his tamer was in his hands. As if responding to the organ his heart began to beat wildly.

'Go on then. Let your blood lust CONSUME you.'
Harry found this urge irresistible and overwhelming. He sunk his teeth into the still beating organ.

Sirius and Remus ran into the clearing just in time to witness the horrific sight. The happy and witty soul of the young son of their very best friend was gone and was now replaced with a corrupt demon.
The sickening sight of him with blood running down his arm and him completely consuming a human heart was enough to convince them that everyone was in aplenty of trouble.

"We have to put him down." Remus said.

"I- I can't." Sirius choked.

"Then we'll have to-"
A green explosion rumbled the forest followed maniacal laughter. Harry was on his knees laughing and...crying. Tears of a tar like liquid poured out of his eyes.
Harry hunched over with his tongue hanging out. It became thin and fork like. A green fire burned around him,burning his robes away till he had nothing but his trousers on.

The skin on his chest and back began to form in a black scaly spiral where he was first penetrated by his counterpart. The blood on his hands formed black shiny scales.

'YESSS FEEL THE POWER SSURGE THROUGH YOU! WE WILL EXACT OUR REVENGE!'
The fire intensified revealing the shadow of a large snake extending from Harry. Crystals shards tore their way through his back running through his spine.

This was it. The boy let a menacing hiss fill the air before the fire extinguished as if it never happened.
A black robe replaced his old one and the body of Luna was nothing but ashes which scattered shortly after.

Remus and Sirius knew it would be foolish to confront the boy now. He stood and left the clearing, his robes moving shadily behind him leaving the two men in pure terror.
'I knew they were there but... their time to die is still not here.'

'That does not matter. We have an old friend we need to settle with before anything else.'

Remus let out the breath he had been holding and look pitifully at his friend. Sirius was in hysterics. He was Harry's godfather.

"How could Dumbledore not tell me about this?" Remus looked at his friend questionly.
"What do you mean? How could Dumbledore know about this?"

"Don't screw with me, Moony! Of course he knew!" Sirius yelled.

The freed man marched angrily towards the school.

"Let me show him a piece of my mind!"
" We'll go talk to him but getting angry always leads to bad decisions.Don't let anger get the best of you and ... you're going the wrong way Padfoot."

"Okay." Sirius let out a deep breath.