A/N: I originally wrote this Oneshot in German and translated it to the best of my abilities. There are probably a lot of errors, so if you find some feel free to point them out. After all, I want to improve. Enjoy the story and don't forget to leave a review!

Disclaimer: I do not own Harry Potter. J. K. Rowling does.

Neither can live while the other survives

(Harry) did not know why he was doing it, why he was approaching the dying man: he did not know what he felt as he saw Snape's white face, and the fingers trying to staunch the bloody wound at his neck. Harry took off the Invisibility Cloak and looked down upon the man he hated, whose widening black eyes found Harry as he tried to speak. Harry bent over him; and Size seized the front of his robes and pulled him close. [Harry Potter and the Deathly Hallows, The Elder Wand, p.528]

"Potter..." Snape's voice was barely more than a whisper, his breath a rattling, gurgling sound. "Dumbledore wanted you to know..." He tried to draw breath, but it ended in a cough.

A few drops of blood landed on Harrys face, but he did not wipe them off. He absently rubbed his forehead as a particularly sharp pain went through his scar.

"Dumbledore," Snape whispered again, "Connection... between the Dark Lord and you... when he tried to kill you..." The words came only in bits and pieces now, the sentences merely fragments. "when the killing curse re... rebounded... a piece... of his soul... was split off. The Dark Lord... cannot... die as long as you live."

Harry stared at him. Beside him he heard Ron's and Hermione's horrified gasps.

"Take... it... take... it"

A silvery substance was suddenly leaking from Snape: Memories! Harry wasn't sure what he should do when Hermione made a strangled sound. Instinctively Harry spun round, a curse already on his lips, but his adversary was faster. Even before he had completely turned, he was hurtled against the wall of the Shrieking Shack, where he lay for a moment dizzily. As though through a haze he heard Ron's and Hermione's incantations when they attacked the opponent together. Then two thuds. Harry looked up and stared directly into pitiless red eyes.

He fired a stunner that Voldemort easily wiped away with a motion of his wand. A moment later Harry felt the hawthorn wand leave his hand and saw it spinning through the air, directly into a white long-fingered hand.

"The Dark Lord cannot die as long as you live," Voldemort repeated Snape's words. He regarded Harry with a thoughtful expression. Harry saw Voldemort raise the Elder wand. Then everything went dark and he knew no more.

He woke on a cold stone floor. When he opened his eyes, he realized that he was probably in some kind of prison cell. There wasn't more time to look around for Voldemort's Cruciatus curse hit him before he could even move. Every centimetre of his skin seemed to be on fire... any moment his head would burst. Somebody screamed; only when Voldemort lifted the curse, he realized that it had been himself. It did not seem to matter how often you were hit by the Cruciatus, it was just as excruciating, as unbearable every single time. You couldn't get used to it.

Shaking from the after-effects, he heard Voldemort's high cold voice. "Alive Harry. That does not mean the same as undamaged."

Again the torment of the Cruciatus. When Harry believed he could not endure it any more, something strange happened. The pain faded away, he seemed to stand next to himself, saw himself writhing and screaming on the ground. Then he was back in his body, felt the after-effects of the curse, the throbbing of his scar, and realized that he had seen himself through Voldemort's eyes. He cast a glance at Voldemort, but the dark wizard had apparently not noticed anything.

With a move of his wand Voldemort flipped him on his back. Gasping and panting Harry lay before his tormentor and gazed up into those cruel red eyes. Then something like a will to live or maybe pride made itself known in him. Slowly he sat up. Always expecting a new wave of pain, he tried to get on shaky legs, while Voldemort watched his attempts silently. Finally he succeeded, supported by the wall.

He forced himself to speak, although he found it hard and his voice was barely more than a croak. "Where are the others?" he wanted to know, "What happened to them?"

"They will be punished," Voldemort said indifferently, his gaze intently on Harry, "No one defies Lord Voldemort."

Harry's scar seemed to have caught fire. Voldemort's proximity was almost unbearable. He had to close his eyes. Swift as a snake a skeleton-like hand suddenly shot forward, gripped Harry's hair and jerked his head round. Harry hissed in pain and opened his eyes again, surprised. Pitiless red eyes met stubborn green. Struggling vehemently, Harry tried to get away from Voldemort but the dark wizard's grip was relentless.

"You should rather worry about your own fate, Harry Potter," Voldemort said softly, "You will live. Oh yes, you will, for you life will ensure mine." The grip on Harry's hair tightened, and he thought his scar would burst. He felt Voldemort bend closer to him as he whispered, "But you will long for death."

"Great," Harry hissed between clenched teeth. The pain in his scar was bringing tears to his eyes. "Everyone should have some last wish. But what will the wizarding world think when they hear that again you haven't managed to kill me? But no, you were never one for the truth. It's so much easier to give them lies. By the way, do your bootlickers know that you are a half blood, Tom?"

Anger flashed in Voldemort's eyes. He seemed about to reprimand Harry. But suddenly a curious expression appeared on his face when he noticed Harry's pain. Harry could only watch helplessly as a long white finger approached his face. When Voldemort touched his scar, he could not stop a cry of pain. He felt Voldemort trace his scar with his finger, and thought the agony would make him pass out. Without noticing it, he doubled his struggle to get away from Voldemort. When the man unexpectedly let go of him, Harry tumbled to the ground, where he lay breathing heavily, one hand pressed to his scar.

"Interesting," Voldemort murmured, "I will investigate this further soon. In the meantime, Harry, there are some among my followers who are positively dying to meet you. Fare well, Harry Potter... if you can."

With that, he stepped out of Harry's cell, leaving the prisoner alone. But not quite as alone as Harry first believed. The unnatural cold and despair he suddenly felt could only mean one thing: dementors. Already he heard their rattling breath, that seemed to suck in all warmth and happiness. Then the memories came and he sensed only dully how a line of dark spectres assembled in front of his cell. With his last strength Harry coiled up on the ground and wished he was dead.

He was standing in a large wide room... the open skies seemed to arch above him... the Great Hall of Hogwarts. At the edge of his vision were dark shapes: his faithful Death Eaters.

But at the moment his attention was only on one of them... on the unusually pale, blond boy kneeling in front of him, trembling. Ah... the fear he demanded!

"...I swear it wasn't my fault," the boy was saying, his voice cracking with fear, "Crabbe conjured the Fiendfyre. I didn't know... I would have stopped him. I was fighting Potter and the mudblood..."

"Look at me!" Harry demanded. His voice was high and cold.

Fearful the boy looked up, his eyes wide. It should have been easy to enter his mind, yet he met resistance. An occlumency shield... very interesting. Maybe Draco wasn't a lost case, after all.

"Let me in," he commanded.

He saw the boy's eyes flicker in the direction where his useless father stood in the ranks of Death Eaters, watching the spectacle.

"I will not ask you again," he said , his voice dangerously low .

He felt the resistance cease and crumble, then he was suddenly in the Room of Requirement, watching the fight of three Gryffindors against Malfoy, Crabbe and Goyle, saw Crabbe conjure the Fiendfyre, saw them escape the flames barely, saw the diadem break...

With a cry of rage he was back in the Great Hall. Draco Malfoy was still kneeling before him, his face white and his grey eyes wide and at this moment he did not care that it was not really Malfoy's fault; someone had to pay. And so he pointed the Elder Wand at the boy and hit him with the Cruciatus curse. And again. And again...

With a pounding heart Harry woke in his cell. His scar hurt and he could still feel Voldemort's overwhelming rage in himself, offering a certain amount of protection from the dementors for a short time. A nauseous feeling arose in him when he thought of what was happening to Malfoy at this very moment.

The connection between him and Voldemort had grown stronger over the last year during the Horcrux hunt. By now it was so easy to get into Voldemort's head that he sometimes didn't even notice how it happened. For a few minutes Harry pondered what it meant, then the dementors regained their control over him and he was again prisoner in a world of fear and despair.

Harry wasn't sure, how long he had been Voldemort's captive. In his cell, under the dementors' influence, he had lost all sense of time. Only when he was in Voldemort's head, he knew how much time had passed.

By now it often occurred that he fled into Voldemort's thoughts when the situation became unbearable. The dementors' presence was constant, they were only called back when Voldemort came to one of his rare visits in Harry's cell or sent his Death Eaters to torment him. Harry connected neither of these visits with good memories.

It was so tempting to forget the pain, the sorrow and the feeling of despair for a while and so easy to slip into Voldemort's consciousness. What he found there often nauseated him and filled him with disgust, but for the most part it was still better than his cell. And Voldemort's life did not only consist of torture and death. These days he spent a lot of time in libraries, searching for new ways to retain his immortality, since now he had only two Horcruxes left. To Harry's relief, his search had been without success, so far, but he was learning many things and Harry with him. Harry could have done without most of it, as it was mostly dark magic he would never use, even if he should get the chance one day. Some of it, however, might turn out to be useful.

Not only new knowledge went to Harry, but also other background, Voldemort had collected in his life. Due to his permanent presence in Voldemort's head, Harry was - without wanting to - more than ever before exposed to the Dark Lord's train of thoughts and memories. He had to admit that Dumbledore had been right. Voldemort was brilliant. His evil genius both horrified and fascinated Harry. Unconsciously his own way of thinking was influenced by it. In the rare moments when he was protected from the dementors' effect, his thoughts were more precise, more defined. If he had had enough time, perhaps he could even have devised a plan to escape. But these moments were brief, usually after he returned to his own body from a trip to Voldemort's thoughts, or shortly before Death Eaters entered his cell. Nevertheless, he treasured these moments, since it was the only time when he was really himself.

And so time passed, day after day.

Triumphant and with great satisfaction Lord Voldemort looked at the two prisoners before him. It was time for another demonstration of his power! Long had he delayed this moment, had waited until he would make the greatest possible impression on the wizarding world, but now the time had finally come. Harry Potter's best friends would die. It was a pity that Harry Potter himself would not witness this. Lord Voldemort did not take any chances, though. Potter was safest in his cell. Too much was at stake! As long as he had not found another way to become immortal, he still needed the boy.

"I see you prepared them well," Voldemort said amused.

The two prisoners didn't look good. Numerous cuts and bruises covered their frames, both were showing the after-effects of the Cruciatus curse. Yet, a small amount of resistance seemed to remain. The red-haired boy moved in front of the girl, as if trying to protect her with his body. A futile attempt.

His Death Eaters were happy about the praise. "It has been our greatest pleasure, Mylord," said Bellatrix, watching him full of devotion.

Abruptly his hatred flared up. He'd had the prisoners interrogated and was aware of the role they had played in the destruction of his Horcruxes. They would pay for this!

He raised his wand and pointed it at the boy.

"Crucio!"

Contrary to Voldemort's belief, Harry was well aware of what was going to happen to his friends. The whole day he had witnessed Voldemort's plans in the man's head, without knowing what he should to do stop him. Now that it was actually happening, Harry was in anguish. He had no way of helping them. His attempts to call for Voldemort had fallen on the dementors' deaf ears. He had raged and screamed, but to no avail. Spent and exhausted, he felt helpless as never before in his life. He knew what was going to happen, yet could do nothing to stop it.

He struggled with himself for a short time, wondering whether he should watch the execution through Voldemort or rather stay away. In the end, he decided to watch. He owed it to Ron and Hermione and he doubted that he had the strength to keep out of Voldemort's head, anyway. More and more often his mind seemed to look for Voldemort's without his doing. It took much more effort to stay in his own body now.

So he watched as Voldemort tortured Ron, his best friend, with the Cruciatus and his heart was bleeding. Voldemort was about to take the dearest thing he still had in this world. He suffered with them, cried and begged, although no one could hear him, and wished that they would at least be granted a quick, painless death.

Usually he felt Voldemort's thoughts and feelings when he was in his head. Not this time. This sadness, this desperation could not be Voldemort's. 'Not Ron," he thought desperately. 'Not Hermione. Everything, but not this.' A wave of never known sorrow rose in him.

It happened suddenly, without warning. One second he was torturing the blood traitor, the next he doubled over because a pain worse than anything he had endured before, worse even than his own rebounding killing curse, seized him. As though through a haze he perceived a voice... or was it a thought? "Not Ron. Not Hermione. I can't live without them."

The pain abated somewhat and when he looked up his gaze met Bellatrix's worried face.

"Mylord... what has happened to you, Mylord? Are you all right?"

He rudely pushed her away and rose with an effort. "Take them away!" he said with a gesture at the prisoners.

"Mylord?" Bellatrix was looking even more worried.

"Do you hear? Get them out of my sight!"

The Death Eaters hurriedly obeyed. He saw the dismayed glances they cast at each other. They did not understand what had happened. Neither did Voldemort. He needed privacy to solve this riddle.

"Leave me!" he ordered. Not until he was alone, did he allow himself to close his eyes. The pain was still there, though now it had receded to a slightly more tolerable level. He held his snakelike head, that felt like it was about to burst.

Once before he had felt a similar pain... only briefly, however, before he had been able to flee it... back then in the Department of Mysteries when he had tried to possess Potter through the connection they shared...

His eyes flew open.

Potter!

With a loud bang the door to Harry's cell was flung open and Voldemort stormed in.

Harry wasn't surprised. He had witnessed Voldemort's breakdown, had first been baffled then thrilled, had seen at which conclusion his enemy had arrived. He felt satisfaction that he was able to hurt Voldemort this way and thereby pay back some of what he'd had to endure.

He knew what caused Voldemort this agony. Dumbledore had explained it to him, though then he had found it hard to believe that love could cause physical pain. But it was apparently so in Voldemort's case and this gave Harry a weapon against his tormentor. If only he had discovered this possibility earlier... but maybe their connection had had to become so strong first, or his feelings for his friends so powerful.

"You!" hissed Voldemort, "You are responsible for this!"

Harry did not even try to deny it. He had wondered why Voldemort had not already discovered his constant presence in his mind. Perhaps because Harry had never become active there before. He did not intend to leave it at that.

He felt another tremor of pain pass through Voldemort before he returned to his own body and saw him grimace.

"Stay out of my head!" screamed Voldemort. It was the first time Harry witnessed how Voldemort lost control.

"I can't," he just said and it was the truth. He didn't know how, by now he spent more time in Voldemort's head than in his own. It wasn't anything he still had control over.

Voldemort closed his eyes for a moment as the pain became too much. When he opened them, he pointed his wand at Harry. A red flash of light and Harry lost consciousness.

At first it seemed to help that Voldemort kept him unconscious most of the time by using charms and potions. But not for long. Again the treacherous scar found a way. If anything, this course of action led to Harry spending even more time in Voldemort's body as his own had no way of calling him back any longer.

Harry continued to hurt Voldemort, since it was the only thing left to him. Sometimes he couldn't tell who he was any more. But he did not give up, continued to hang on to the last remains of identity with all his might.

The constant pain made Voldemort restless and irritable. He spent most of the time in his chambers, away from the Death Eaters, searching for a way to dispel Harry from his head. But everything he tried failed. The connection between Harry and Voldemort war unique, no book in the world could help him. There was only one way to get rid of a split off soul piece.

Again Voldemort sought him out in his cell. With an effort Harry forced himself back into his body. He could see that his adversary was close to madness. His body appeared even more skeletal than before, in his red eyes shone pain. Lord Voldemort was finished and they both knew it.

"You can end it," Harry said calmly, "Kill me. You know it is the only way."

"I cannot." Voldemort's voice was barely more than a pained hiss. "I would weaken myself too much."

Harry was looking through Voldemort's eyes again. He forced himself back. It took all his willpower.

"And what do you think you are doing now? This is no life, not for you and not for me. Neither can live while the other survives. It's this damn prophecy. So do us both a favour and end it!"

To emphasize his point of view, he gave Voldemort a taste of his desperation, his longing for death and to be with those who had left this world before him. Voldemort visibly winced.

Harry saw him slowly raise his wand. For a moment he was Voldemort, trying to muster the willpower. His hand was shaking. Harry returned to his own body, that had sheltered him all these years. What a pity he had to leave it now forever. But there was no other way. And he was ready for death. Had been for a long time.

He gazed in his enemy's red eyes, the last thing he would see in his life and almost felt pity for him. Voldemort was about to destroy a part of himself, of his soul. Maybe that was what induced him to speak: "It's not too late, you know."

"What?" Voldemort gaped at him, his wand pointed at Harry.

"You can still heal your soul. You would truly have to regret your doings, show some remorse." But he had spent enough time in Voldemort's head to already know the answer.

Voldemort's face distorted into a sneer, though it looked more like a grimace. "Lord Voldemort regrets nothing. Not even your death if you are suffering from this delusion. It is the loss of another horcrux I regret. Your end I see with pleasure."

Harry shrugged and calmly replied: "Then what are you waiting for?"

And at last Voldemort spoke the final words. His voice was barely more than a whisper but it rang in Harry's ears.

"Avada Kedavra"

He woke in his cell again, his thoughts still preoccupied with the strange talk he'd had with Dumbledore at King's Cross. From the corner of his eyes he noticed Voldemort stir, apparently he had also fallen unconscious. Then he caught sight of the Elder Wand still in Voldemort's hand. This was his chance!

He lunged at it and gained it without much resistance, and without noticing that his scar did not even twinge despite the physical closeness.

Voldemort looked at him in disbelief. "How...?"

"Stupefy," Harry replied.

The power of the red flash spurting from the elder wand surprised Harry. Voldemort harmlessly rolled against the bars.

Harry stared at the wand. So he was now the true master of the Elder Wand. He looked down at his unconscious enemy. It would be so easy... but it didn't feel right. He had always known that he was no killer, but now, as this man, who had caused him and those close to him so much suffering, was at his mercy, he was proved right. It was wrong to kill a defenceless man, even if that man was Voldemort.

He shrugged. It didn't matter. They would meet again and he would get another chance. And there was still one Horcrux left: Nagini. But first he had to free Ron and Hermione. From Voldemort's memories he knew where they were being kept.

Slowly he got up. His legs were still shaky but they carried him. He cast a Disillusionment Charm on himself and opened the door of his cell with a motion of his wand. Then he breathed deeply and took the first step into freedom and into a new life.

The idea for this Oneshot was born when I was wondering what would have happened if Voldemort had realized that Harry was a Horcrux and let him live. I believe the parasite-like nature of their connection would have fullfilled this part of the prophecy sooner or later: "Neither can live while the other survives."