Disclaimer: I own neither Harry Potter nor Naruto nor any of the characters in either. All other ideas belong to me.
Summary: 4000 years after the death of his friends, Naruto is on the hunt for death so he can join them. However, as the Kyuubi, he must search for something that can kill him. He has heard of a Dark Lord of whom everyone is scared. A visit might be in order.
Severus Snape watched impassively as Lord Voldemort tortured yet another pitiful muggle. He really didn't like to see such casual cruelty, but his reputation was at stake. If Voldemort ever got wind of his betrayal, his usefulness to Dumbledore would be at an end along with his life. So, Severus continued to shield his mind and emotions. One emotion alone could shine through his mask without retribution: contempt. Watching his fellow Death Eaters, Snape felt nothing but contempt for the groveling fools. However, Voldemort enjoyed pitting his followers against each other, so there was no threat of retribution for such feelings.
The muggle screamed in utter pain under the Cruciatus Curse as Voldemort and his sycophantic lackeys laughed and Bellatrix Lestrange cooed in awe at her master's beautiful masterpiece of pain. Suddenly, the screaming ceased and all the wizards fell silent as they noticed the dagger that had flashed from a nearby tree to embed itself in the throat of the muggle, killing him almost instantly. The wizards shrank back from their leader to avoid his rage at the stolen kill.
Voldemort fumed inwardly. Who had dared to kill his victim? No wizard alive should stoop so low as to kill in such a messy, crude fashion as a physical weapon. His scarlet eyes swept around the clearing, taking in all his followers. He looked intently at each one, stopping on Severus Snape. Snape seemed the most likely suspect, as his Occlumency was advanced enough to prevent verification of his loyalty. Voldemort also knew that Snape was ruthless enough to commit such a bloody murder without a second thought. Usually that was an asset to the Death Eaters, but if Snape were to challenge for the leadership, he would have to be removed.
Lord Voldemort raised his wand and pointed it at Severus Snape, intent on finding his answers. However, before he could speak a single word, a figure appeared in the center of the clearing. Voldemort hissed in surprise as he realized the appearance was not accompanied by the customary crack of noise associated with Apparition. Rather, the person standing calmly in the midst of the darkest gathering ever seen in the wizarding world had seemed to just appear with no noise, movement, or warning. He just wasn't there one moment and was the next.
Snape stared in amazement at the newcomer. He had seen the abbreviated movement of his Lord and had already prepared for death. Then, suddenly, Voldemort's attention was caught just in time by this hooded figure. He appraised the person, but there wasn't much to see. The Death Eaters quickly formed a ring around the new arrival and drew their wands, but were waved back by the Dark Lord.
Voldemort was curious. It had always been one of his greatest failings, and this new person piqued his interest. He stared regally at the cloaked person and demanded, "Who are you and why are you here?"
To the astonishment of all watching, the muggle laughed. The hood of the cloak was thrown back to reveal a short young man. Snape estimated his age to be about twenty years old and well under six feet. Spiky hair of gold and red shone in the moonlight. The chiseled face with tan skin did not even twitch under the scrutiny of the Dark Lord. But possibly the most surprising features were the whisker-like scars adorning the tanned cheeks and the slitted pupils in the vibrant red eyes. A quick glance at Voldemort showed the dark wizard's surprise.
Two pairs of blood-red eyes held a silent duel for a few minutes. Voldemort capitulated first and glanced away. The other duelist smirked at the unconscious capitulation. Voldemort burned with embarrassment as he lost face in front of his underlings. Attempting to regain the lost respect, he said, "Answer my question, or die."
The smirk widened and the newcomer said in a deep baritone, "My name is Namikaze-Uzumaki Naruto, the Kyuubi. And you must be the vaunted Tom Riddle, more commonly known as Lord Voldemort, the Dark Lord. I came to ask a boon of a fellow demon Lord, but what do I find? Mere humans cavorting and corrupting the name of power. This world must be truly weak if this is the strongest it has to offer."
The Death Eaters gasped at the blatant disrespect shown. Voldemort almost lost control of his rage, but his curiosity was too powerful. "What do you want of me?" he asked.
Naruto suddenly stopped smirking. "I heard you were the most powerful so-called wizard in the world," he replied. "I am searching for something. I am willing to pay for your assistance."
A business proposal? Well Lord Voldemort would just treat this as any partnership: help find the valuable thing, take it, and kill his partner. "Very well," he said. "What are you looking for and what do you have offer in return?"
The smirk returned. "I offer you your life." Two hands emerged from the cloak, holding several small objects. Voldemort's fury rose as he recognized his Horcruxes: the locket of Slytherin, Hufflepuff's cup, and Ravenclaw's tiara of wisdom. The stranger continued, "I understand each of these objects holds a piece of your soul. The others which were contained in a diary, a signet ring, and a young boy have already been destroyed by your enemies. I would advise you to keep your something as valuable as your soul closer to you." He chuckled at the look of hatred, horror, and fear on the taller man's pale face.
Naruto continued, "I have traveled from world to world in search of one thing: death. My bargain is this: attack me with your most powerful attacks. I will not resist. If you succeed in killing me, you will live. Fail and I will destroy these trinkets and you."
"What if I refuse?" asked Voldemort, stalling for time. The proposition was a terrible gamble. Because the stranger named Naruto had managed to find his Horcruxes and knew about the final three, Voldemort's usual confidence had suddenly deserted him.
Naruto grinned, showing elongated canines reminiscent of a carnivorous animal. "Well, let's just say, they way I see it, you don't have much of a choice."
Severus watched in astonishment as the young stranger took complete control of the situation in less than two minutes. He had never seen such fury and fear in his master's face before. Voldemort was truly stuck between a rock and a hard place. On one hand, he could accept the challenge. If he succeeded, he got his Horcruxes back, but if he failed, he died almost instantly. On the other hand, if he refused the offer, the stranger had effectively threatened to destroy his Horcruxes anyway.
As a last chance to delay the inevitable decision, Voldemort pointed his wand at the unmoving blackmailer and attempted Leglimency. To his utter horror, the spell was deflected by the most powerful mental wards he had ever dreamt of encountering. Snape's defenses were nothing compared to this…creature's. All Voldemort could discover was that the pattern on the mental shields was definitely not human. "What are you?" he gasped in astonishment.
Red eyes colder than his own focused on his face. "I would have thought," began Naruto, "that even it a primitive world like this, people would know not to try to enter the mind of a demon. I am the Kyuubi, the most powerful demon alive. Four thousand years ago, I was once a human. However, I gained immortality when I defeated the previous Kyuubi."
Immortality! The single word captured the interest of the Dark Lord. One who had achieved his own goal stood directly in front of him. Also, didn't the stranger say he achieved immortality by killing the previous demon? If so, all Voldemort had to do was to accept the offer, kill the unresisting demon, and he would live forever. Why the demon wished to die was a mystery to the wizard whose life goal was to evade death, but no matter. It was time for the Dark Lord Voldemort to fulfill his destiny.
Severus Snape saw the greed shining in the eyes of his master and knew the decision had been made. He backed away from the two red-eyed monsters before him. Each wanted what the other had and was willing to kill to get it. Snape realized that if Voldemort killed the stranger, the entire world would be in deep trouble. However, there was nothing he could when both Voldemort and the demon wanted this duel.
True to his word, when Voldemort cast a blinding green Killing Curse at him, Naruto simple stood and allowed it to hit him square in the chest. The Death Eaters waited for his corpse to crumple as so many had done before. However, as the beam of light hit, a visible wave of orange-red power materialized around the demon and engulfed the curse. The Death Eaters gaped and Naruto just sighed. "That's what I was afraid of," he said sadly. He looked down at Ravenclaw's tiara and with a sigh plunged a glowing clawed finger through it.
Voldemort writhed in pain as he felt a portion of his soul shrivel and die under the power of the demon. He glared at his tormentor who merely shrugged and said, "I think you need more motivation to have any chance of defeating my body's automatic defenses. Or should I just put you out of your misery like I did that poor man earlier?"
Lord Voldemort hissed in rage and motioned his followers to attack his torturer. However, before they could even move, nine glowing orange tails emerged from under the demon's cloak and stabbed the Death Eaters. Snape watched one heading for his own heart, but it stopped right before penetrating his skin. He could feel the power radiating off it as the demon turned his gaze toward the lone surviving Death Eater. Severus felt his Occlumency mental barrier bend and snap under the pressure of the foreign mind. The mental intrusion quickly swept through his memories and thoughts, and then retreated. The demon smiled and showed a small part of his own mind. Severus was astonished to see a quick summary of the life of the demon flashing in his mind. He had assumed this being to be cold and heartless, but he realized the tough exterior protected a lonely individual with morals more human than his own. He felt tears trickling down his cheek as saw what Naruto had unwillingly paid for eternal life. He also felt the loneliness that drove the great being to seek relief in death.
After a long moment, the demon turned back to Voldemort who responded with a vicious slashing spell. A large cut appeared on the demon's body, but quickly healed itself. Naruto selected the next Horcrux, the pendant, and destroyed it as well. Voldemort was now terrified. He shot a stream of fire at the creature, but the ground rose to deflect the flame. The final Horcrux followed the previous ones. The final pieces of Voldemort's soul now resided in Nagini and his own body. The Dark Lord cast his strongest protective spells around the snake in a final attempt to protect himself. Naruto simply said, "I hate snakes. Kuchiyose no jutsu," and a large, white, six-tailed fox appeared in a puff of smoke. "Tsukiko, fetch the snake."
The fox darted forward and attacked the spell barrier with its teeth. When it was repelled, it growled with annoyance. With a howl, its eyes began to glow and it attacked once more. This time, when it hit the barrier, instead of bouncing off, it turned transparent and phased right through. The snake struck at the fox, but the white animal dodged and bit the reptile behind the head. With a quick crunch, the snake was paralyzed. Emerging the way it entered, the fox dragged the snake with him before Voldemort could even process the fact that his barrier was breached. The snake was laid at the feet of the demon and the fox disappeared with a bow and a puff of smoke. With a smile eerily similar to the one formerly displayed by the fox, the Kyuubi plunged a claw directly into the head of the snake and injected his potent chakra. Within two seconds, the body of the snake dissolved and Voldemort was left with no more walls behind which to hide.
Snape watched in satisfaction as the lonely demon walked lazily toward the cowering wizard. He watched as the ninja gathered his chakra in the palm of his right hand. The glowing reddish-orange orb of raw chakra devoured the Dark Lord, reducing his body to ash. Naruto examined his handiwork and turned toward Snape. He said, "You will never forget him, just as I will never forget my friends. Live for her sake, so when you meet her you will not be ashamed. I resume my search for my own death. Farewell, Severus Snape." With a huge surge of chakra, the Kyuubi disappeared in a swirl of black flame.
Severus Snape bent his head for a moment to pray for his success, then turned away from the scene of the demise of the darkest wizard of all time. It was only just that it was his own greed and immortality that finally defeated him. Apparating to Hogsmeade, Snape snorted when he imagined the look on Dumbledore's face when he heard that Tom Riddle was dead. It was not easy to surprise the venerable old man, but Snape was confident he would make Dumbledore either faint or go into cardiac arrest.
Thinking back on the incredible being who had helped their world immeasurably, Severus Snape remembered his final words. As he gazed up at the castle of Hogwarts, he felt lighter than he had in decades. He started up the path to the school, determined to live his life as the ninja had recommended: for Lily.