A/N – This is only my second fanfic, and my first Harry Potter one. I know the books well but may make some mistakes – all I ask is that any criticism is kept to constructive comments about my writing style or plot, not about any slight errors I may make from the originals (this is Harry Potter as according to me).

Disclaimer – This all belongs to the wonderful JK Rowling, except my OCs.

Prologue

Snape lay against the wall in the shrieking shack, his life ebbing away with the snakes poison. He had done his job, he had given Potter the memories that would help him finally defeat the Dark Lord, and now the world was slowly fading away as the poison worked through his system. He could almost feel the moment it reached his heart and stopped it beating.

Except if this was death, it felt wrong. Instead of becoming fainter and calmer, everything was becoming more vivid. More worryingly, it was also becoming more painful. The dull ache in his side had become searing agony from where the Dark Lord's curse had hit, and he could feel the blood running down his neck from Nagini's bites. There was a crashing of noise around him from the war that was still raging. He didn't know how long he had been out of it, but the fighting appeared to be in full flow. The pain he could feel in his arm was eclipsed by the pain in the rest of him and at this point it didn't signify anything. He was in no state to realise that his Dark Lord had met his end at the hands of a 17 year old boy.

He suddenly became aware that he wasn't alone. Someone was busy tending to the wounds on his neck, stemming the blood flow. With an effort he opened his eyes and found himself looking into piercing blue eyes. He stared blankly for a moment before the realisation hit him – he knew those eyes. But it was impossible.

"Albus?" His voice was a croaked whisper. The eyes sparkled merrily in response.

"Not quite Severus." Snape had just long enough to realise that the voice was female and this didn't seem to make sense, before he drifted into unconsciousness again.

-x-x-

Guinevere looked around the small office, searching for something. Behind her in one of the large chairs that typically decorated the headmaster's office a figure slumped, head lolling forwards on his chest which moved slowly with his ragged breaths. The office had not escaped the wrath of the war, there was detritus everywhere and one wall was struggling to remain upright. That didn't matter to her though, as she searched through the portraits that lined the walls.

The fighting had stopped now, and there was a strange stillness over the castle. In the great hall far beneath her the survivors of the war were gathering, celebrating and mourning their losses. Up in the study the only sound was Guinevere's impatience as she looked for the person she was after. Eventually she stopped in front of a frame just behind the headmaster's desk.

"I know you're in there. I want to speak to you."

Albus Dumbledore slid into the empty frame, and looked at the woman perched on the edge of his desk with surprise. "What are you doing here, Guinevere?"

"Something wasn't right, I came to fix it." She waved behind her slightly, and the portrait saw the unconscious figure for the first time.

"What did you do?!" The figure in the mirror was shouting now, drawing the attention of all the other portraits of past headmasters and 'mistresses of Hogwarts.

Guinevere sighed, she had known this would require a little work. "It wasn't fair," she replied calmly, flicking her bright red hair back over her shoulder. "He did so much, I wasn't going to let him die." The figure in the portrait opened his mouth, about to berate her further when she held up her hand. "I know that I've probably changed the future irrevocably, but sometimes it needs changing."

"You can't just waltz into this dimension and change everything! You don't belong here, child."

She sighed, rubbing her temples with one hand. "I'm here to even the balance, as it were. I am not the only creature here tonight from another dimension."

The figure of Albus Dumbledore paused at that, and if a portrait could have paled he would have then. "Demons? Demons came?"

The woman perched on his desk nodded wearily. "With everything Voldemort did, how could they not? He created enough rips in the fabric of this dimension that others have begun to leak through. I'm here to redress the balance. And saving him," she jerked her hand over her shoulder towards the unconscious figure, "is just the start."

The elderly wizard gazed at her from his small portrait, concern evident in the piercing blue eyes. "Be very careful, Guinevere. There are many things here that will harm one of your kind."

Matching eyes looked at him from a pale face surrounded by red hair so bright that it almost glowed. "Don't worry father, I know what I'm doing." She cocked her head slightly as she heard voices coming up the stairs. "Someone's coming…it sounds like Potter. He'll be wanting your advice." She grinned at the portrait who was proudly looking towards the stairs and disappeared in a flash. Amongst the rapturous applause of all the portraits in the office the three teenagers didn't notice her leaving.