And then it hit him, like a giant, icy cold, slap in the face. In the midst of celebrations and his victorious triumph he thought over the events of the night and it seemed to suck the air out of his lungs. But the damage had been done, hadn't it? There was nothing he could do. The last act Voldemort had ever done was to ensure Harry Potter's misery and self-doubt.
The Great Hall had been filled with the blinding, garish light of a myriad of different colored pajamas and the great, black spots of fallen Death Eaters. The colors were distracting, trying to blind him, to draw his attention away from his ultimate goal; Voldemort. And then they struck in tandem, each shouting their spells, hoping to destroy the other, but the spells collided. And then, in the split second before the Dark Lord's Killing Curse rebounded, Voldemort was reduced. He was no longer serpentine, he was once again the lonely orphan boy, Tom Riddle. And he hissed the word in Parseltongue so that no one else would understand, but Harry understood. "Murderer."
But he was being ridiculous, wasn't he? No one in their right mind would mourn the passing of Voldemort. He was family-less and friendless. And aside from that, Voldemort had done nothing but create misery and terror. He hadn't bettered the world. Voldemort had done his best to destroy every ounce of goodness and happiness in the world. It was ludicrous to be feeling guilty for ending this monster's life, but there it was. He was feeling guilty.
He shook his head forcefully, trying to convince himself, or shake these thoughts out of his head. It's not like he had done it in cold blood, it's not like he had sought out Voldemort for his own revenge. But he had, hadn't he? Deep down, every time he had thought about destroying Voldemort it had always been to avenge his parents, to destroy the man who had been responsible for destroying his chance at having a normal life with loving parents; of having a family.
No, but that hadn't been the only reason. Think about all the misery he caused, Harry wanted to scream. He had meant to disarm, he told himself. But even that didn't ring true, he'd known what would happen if the Elder Wand had accepted him as it's master. Instead he turned down a different path of thought; it was for the benefit of everyone. Fate gave Harry the power and the desire to stop Voldemort. He wanted to cry, shout, yell, plead for absolution. The responsibility had fallen to him. If he had sat back and done nothing to improve the situation he would have been no better than Voldemort himself, and a coward to boot. It had been for the greater good.
But no, that sounded like something from Dumbledore's misguided youth. Rephrase that. One life lost for the salvation of many. But it hadn't been one life lost, or one life voluntarily given to protect those the victim loved, like Harry himself had had to suffer. No, this had been one life unwillingly taken to protect those the victim loathed. This had been murder, no matter how good of a cause it had been for.
It was Voldemort, Harry reminded himself angrily. No one would have mourned his loss. But was that enough to make Voldemort's life worthless? Did what you do on earth determine your true self-worth? Did how many people who mourned for your passing determine the worth of your soul? Did we all fall into some grand hierarchical pyramid from a few worthy souls to a near infinite amount of dregs who even all together couldn't match the worth of one of those few pure souls. No, he told himself. A life was a life, and no matter how badly someone lived, it wasn't up to other mortals to determine that they had reached the end of their life. That was why he'd let Peter Pettigrew live, despite Sirius and Remus wanting to dispatch the traitor then and there. It simply wasn't for them to decide.
But then where did all this leave Harry? If it was true that all souls were equal and it was also true, which it was, that he had killed Voldemort and that to take a life was something not to be done by mortals, then Harry had commit murder and ought to be tossed in Azkaban. But that hadn't happened. Representatives from the Ministry had been at Hogwarts when it had happened. Aurors had joined in the battle and after it had happened, and Voldemort lay dead on the floor of the Great Hall he had received nothing from them but their congratulations and thanks. The injustice of it blew his mind.
Country-wide, maybe even worldwide, Death Eaters were being rounded up and sent to jail, but Harry, who had commit the same crime as many of them, was left to the comforts of a private dorm at Hogwarts with a plush bed and a platter of his favorite foods. Injustice, he brooded. Maybe he would turn himself in. But the more he thought about it the more he grew convinced that the Ministry would laugh in his face and refuse.
And only then did he realize the last punishment that Voldemort would inflict on him. Tom Riddle's last revenge. That while Voldemort had been set to realize his greatest fear; death, he inflicted the same punishment on Harry who was left to deal with his greatest fear; guilt.