Disclaimer: All of this lovely world of Harry Potter belongs of JKR. I am merely dabbling in it for fun.
Summary: Just some Voldemort with a dash of Harry.
THE PORTRAIT
This, he thinks, is perhaps what it might be like to be a Horcrux. A static thing of soul and memory, with a past and no future. He slipped from himself like a snake sheds its skin, leaving a dried, hollow image of what was. Abandoned.
But still himself, in every way. And still afraid to die. Even though he is not a Horcrux nor a Dark Lord. That is why he does not seek out the others, why he remains framed in the gothic darkness of his alotted scene. He is a relic of another time, intended for proud display, now wrapped up in brown paper and left in a heap with other disused objects - his paint was not even dry when they came for him. And then forgot.
He feels sick at the gratitude he feels for their forgetfulness. He was enchanted against vandalism, but would be helpless against any wizard truly determined to erase him. So many spells capable of destroying him - he knows them all. Should anyone hear of his existence... it reminds him of the forest where he hid for so many years when the aurors where abroad and searching for what little of his spirit remained. He misses Nagini. He misses little minds to amuse him. Most of all, he misses magic.
It was, he muses sadly, a mistake to commission a portrait of Lord Voldemort. He has never been very good at sitting still and he had not liked the artist's eyes. The way they had moved over his face, so carefully, after the initial period of fearful gawking. Then he was forming on canvas the way he'd once formed in a boiling, stone-bellied cauldron. But this time it had been slow. Weeks of smudged, layered gestation until - finally - he was complete and his own narrowed, scarlet eyes were scrutinizing his form, with the Headmaster's hawkish shadow lurking in the background.
"What do you think, Severus?"
"An excellent likeness, my Lord."
"You do not find it too... impressionistic?"
The Dark Lord could not see Snape's face, but his painting could. There was no smile, but the Headmaster's black eyes glittered. Voldemort had expected something more staid, perhaps akin to the Headmasters' portraits. But what hung before him was a lurid fantasy of near-translucent, reptilian whiteness, inlaid with two pools of bright, undiluted rubine which stared out of the gilt frame with terrible, cruel majesty. Red, white, black, and blue which slid delicately under sharp cheekbones, shadowed hypnotic eyes, dotted slitted nostrils, and lined a lipless mouth.
Snape understood that Voldemort's musings were not a conversation and said nothing. The Dark Lord turned away, decision made.
"Hang it prominently within the castle, somewhere worthy of its subject."
"Of course, my Lord."
The portrait did not speak to his fellows. They were beneath him. Gazing haughtily down at students and teachers alike, he saw no need to talk. They tried not to look, tried to forget his eyes on them. Then came a fiery dawn and his handsome frame had cracked as it hit the ground.
Movement - footsteps. Voldemort drew his hood over his head and retreated from the foreground into the darkness. The whine of old hinges and then: "What is this junk?" Junk. But fear overpowered his indignation and he sank further back, all but disappearing into the shadows. The brown paper began to tear. He held a breath that did not exist and scarlet eyes widened in horror. "Hello," a man whispered, "why have you been thrown away, huh?"
Voldemort, still hiding, was struck by something in the words. They saddened and angered him. He almost threatened whoever it was, but held his silence when he remembered his threats would be empty. The man sneezed: the paper wrappings were laden with dust. "You must be out. I would be, if I had such a boring background."
"I am here." They were such simple words. He did not understand why he said them. This wizard had stumbled upon him by chance and, inexplicably, he was suddenly loath to let him go. Or perhaps he simply needed to articulate his existence. The words were high, cold, and as thick with dust as everything else.
"It's good to meet you." He did not recognize the voice immediately. It was low and paternal. A baritone, nothing like the hoarse boy he remembered, his adolescent screams breaking all over the place. "I'm Harry Potter - the new Defense Against the Dark Arts professor - these are my quarters... I guess McGonagall really meant it when she said they needed a clean up."
Harry Potter. Even in this slender, half-existence, he was still to be dogged by Harry Potter. Icy fear turned in his stomach, turning almost immediately to silent rage.
"Er - that's a fine frame you have there."
"It is broken," Voldemort answered softly, a quiet hiss from behind said frame. Broken like the cup, the ring, the diadem, and the locket. Broken like Nagini. Junk. Thanks to this boy, this man. He is overrun with anger and helplessness, yearning to shriek with fury and constrained by terrible fear. A wretched, strangled keening escaped the painting.
"I can fix you up, if you like? What's your name?" A hand reached out to brush the dust off the corner of the frame. "Maybe you'd like to be the portrait concealing my door? The Headmistress said I could chose."
I am Lord Voldemort. But he wasn't. He wasn't even a wizard. A shriek built up behind his mouth, but he refused to let it out. Yet it still escaped as a wretched, muted keening. His shoulders shook with effort to contain it and perhaps Potter saw a trace of white pigment.
"Voldemort?" He sounded more curious than horrified.
"Potter," he hissed, full of hatred.
"Well," the wizard replied, his emerald eyes shining, a wicked grin on his face. "I think you'll be perfect. You can help me with my lesson plans. Didn't you always want to teach Defense Against the Dark Arts, Tom?"