I love Phantom (both musicals, and the original book), and I hadn't written anything for it. So I decided to do this little bit, mostly inspired by a line from the 2004 movie, even if I do prefer the stage version. A bit of an alternate ending to the first musical.
Also, I'd like to thank Wikipedia for the opera names.
And now (read this in David Fawcett's voice), the fabulous..Phantom of the Opera.

"Go now! Go now, and leave me!" the Phantom's voice carried across his beautiful lair.

Christine looked back at him; an immeasurable sadness in her eyes. For all his sins, he was still the man who'd inspired her voice; in some, twisted fashion, he was the reason Raoul now stood by her side.

"Come, Christine," Raoul took a few steps back, to her side. He pressed his lips tenderly to her cheek.

She smiled; and kissed him back. Yet her thoughts strangely were occupied by comparisons with that nameless genius in the depths of the opera house.

The burning opera house.

The gondola. Christine lay, watching Raoul row; slowly. Less graceful than the Phantom. Her mind couldn't help but think of him; he was in every brick here, every little speck of this place.

They reached the opera house; Raoul took her hand, leading up the stairs. Fire blazed above. The auditorium was in ruins; the Phantom's masterpiece lay strewn over the red seats, burning. Christine fought the urge to try and preserve some of it.

She couldn't. There wasn't enough time; and she needed to forget about him. She needed to-

A blazing piece of the roof fell. Raoul's cry; she looked at him, just metres away.

And then the burning mass struck her face. She fell to the floor, unconscious.

҉

"Christine?" Raoul's tender voice.

The singer slowly opened her eyes; aware suddenly of a burning pain on one cheek. She lifted a hand to touch it; Raoul reached out, gently stopping her.

"They've done what they can," her fiancée bowed his head; "I'm sorry."

"What is it, Raoul?" her voice still bore its old beauty.

She was laying in a bed; in a hospital, or a house. She wasn't sure. Carefully, she propped herself up; facing the man who sat beside her.

Raoul couldn't suppress a twitch. A sign, however minor, of revulsion. Christine shivered.

He was looking at her. He was repulsed…by her?

Fearfully curious now, she reached out; patting, and finding a mirror by the bed. Raoul's eyes widened; he looked at her. Eyes tender, yet that twitch remained, unsuppressed.

Hands shaking, she brought the mirror in front of her face. Eyes closed; she was afraid to look. And then, moments later, she opened them.

Earlier in her life, she might have recoiled. Maybe gasped; maybe screamed. Now however, such deformity held little meaning for her. It said nothing about the person.

One side of her face was reddened; scarred. Burnt and bruised. A network of those scars ran over half her face; the side on which the fragment of the opera house had hit her. Twisted. That was a good word for it; the skin was twisted out of shape, lines of injury running over it, contorting it into an unnatural shape.

Hideous. Maybe, to other eyes. She couldn't judge.

"They say it'll heal," Raoul began. His shoulders were unnaturally tensed. "Improve, over time; we just need time."

"No Raoul," Christine shook her head. The scars still burned; pain. "Something like this won't heal, not completely."

Raoul continued to look at her; yet that continual twitch of revulsion was ever-present. He loved her for her beauty and her voice; and one of those was gone now.

At least, to his eyes. No one seemed to notice the masked face peering in the room, having followed Christine ever since hearing her scream.

"Stranger than you dreamt it," Christine murmured, a smile playing at her lips. She put the mirror down.

"Hm? What was that?" Raoul spoke, on edge.

"Something a friend said to me," she smiled. The action would normally have put Raoul at ease; yet he seemed unwilling to so much as look at her.

҉

The singer slept; long brown hair flung out over the sheets and pillow. Eyes closed.

"Christine…" A quiet whisper carried into the room; one filled with pity, with immeasurable pain.

She did not awake. The stranger quietly paced into the room, standing over her. Expressionless. One solitary tear fell, silent, onto the sheets.

A tear for her pain, and not her disfigurement.

When Christine awoke, she was once again in the room; yet, just in front of her, there was a single red rose.

҉

Sometimes, the house felt like a prison. It was Raoul's house; she'd discovered that now, he'd taken her here on that day, ooh, at least a year ago. She never left. Once they'd tried that, when they were more naïve; the public shunned her. Those scars.

Raoul looked after her. Food, water, the essentials. She spent the day in the house; playing music and singing.

She was grateful to him; yet he still could not rid himself of that irritating twitch.

Sometime along the way, their marriage had been cancelled. Wordless; the day had just come and gone, and neither of them seemed surprised. They never spoke of it again.

Christine finished the piece she was singing; a soaring piece from Dalibur, by Smetana. It was one she hadn't sung often. She'd learnt many new arias in her new, confined life.

And sometimes, after she finished a piece, she closed her eyes, just listening. Maybe, in her head, another voice, male, echoed her song.

"Hello?" she called out.

The singing abruptly stopped. Silence.

҉

Another day; another piece. She'd chosen Les Hugenots, a grand opera by Meyerbeer. The specific piece she'd decided upon was a duet.

If any piece would gain a reaction from her strange, unseen visitor, this one should. It concerned a woman's marriage to a man named Raoul, irony, and the unhappiness caused by the romance. Christine wasn't sure why; yet she'd chosen a song sung by those angry with Raoul.

Her turn came to an end; she left the notes hanging in the air. At this point, another singer would begin, continuing the opera. She closed her eyes.

And there, like a distant echo, his voice drifted in, perfect, beautiful.

She sang once more, eyes closed in the bliss of being able to sing, once more, with a partner. Raoul had tried once; yet his skills in music were decidedly mediocre.

Their voices soon rose in unison, blending perfectly, a harmony she'd heard only once before. Every note, combined angelically with every note of his, until they were as good as just one voice, merging entirely.

The piece eventually drew to a close. She fell to her seat; scars on her face again streaked through with pain from the passion with which she'd sung. Silence; her unknown partner did not speak.

Then: "Bravo, Christine." A distant whisper.

She stood up; walking to the next room, in an effort to see him. Nothing; that man had left, yet in his place there was a solitary red rose.

҉

Three years on. She closed her eyes, lost in the distant echo of her song; from that man.

They still performed duets, yet only very rarely. They spoke only in song. A note from her; a note from him, perfectly matched. If she was sad, his tones would bring in more melancholy; which somehow brought her, by the end of the song, into the throes of joy: joy which he quite easily echoed.

Raoul returned to the house; passed straight by her room, and went to his own. An increasingly common habit, it seemed, in recent days. His breath stank of alcohol; he could not bear to look at the scarred face of his once-fiancée.

"Goodbye angel," Christine murmured to the empty air; knowing he'd hear.

҉

Ten years since the burning of the opera house; and Christine found herself wishing to see her strange duet partner, even letting him see her still-visible disfigurement.

The scars had barely healed since that long-ago day. Etched permanently in her flesh. One day ago, Raoul had simply not returned home. Christine found herself instead visited by Madame Giry; the man she'd once loved had simply left. That was all the news she'd known.

Alone in the house now, Christine sang her heart out. Don Juan; the Phantom's show.

There'd been a moment's hesitation; and then the distant, unseen voice began to join her in the masterpiece. Verses she'd memorized long ago; still emblazoned in her mind.

The point of no return; how apt. She'd see him once more, if she was allowed. Reveal her new injuries. Despite the roses Christine received almost daily, the man had never appeared to her, and so never seen her.

She simply knew, instinctively, that it was him.

They reached the crescendo, voices merging in the way that only those two could. Christine closed her eyes at the peak, losing herself in the way his voice complimented everything; not just in her, but in the world at large.

We've passed the point of no return.

Silence; yet the air itself seemed to thrum with its own natural applause. Christine smiled; it had been too long since she'd sung a masterpiece.

"Bravo," a distant, spectral voice. Lone claps.

"I want to see you," Christine said suddenly. Forcing herself to risk it.

Silence; for a moment she was afraid she'd gone too far. For the next moment, a twisted smile played at her lips, imaging him somehow coming out of the mirror beside her. And then, the next moment, a click as the door opened; and a wide smile on her face, as she turned around.

It was the Phantom; and he looked no different to before. White mask snugly fitted, concealing the face which held no horror for Christine. The familiar, somehow casually formal suit covered him.

Moving with an almost supernatural grace, he neared Christine, raising one, pale hand, touching it to her scarred cheek. She expected to feel pain; there was no such sensation. Only an awareness of completion.

"I'm sorry," she murmured.

Her life had been affected by the injury. Raoul, the man who'd once loved her unchangeably, had been repulsed by the disfigurement. Too set in his ways to change; when people would scorn the genius of the Phantom for the deformity he bore, it was hardly a surprise that she too faced similar rejection.

"For what?" his voice was soft, musical, barely above a whisper

She couldn't speak; Christine merely gestured weakly up at her injured cheek. The Phantom's eyes ran over her face.

"I see no difference," his melodic voice said, "As radiant as ever, Christine."

Gracefully, all hesitation long since discarded, he moved even closer, pressing his lips gently to hers. Heaven exploded from her mouth outwards, currents of bliss running to her mind, her very body tingling for his touch.

"Angel," she exhaled, as he moved away. She was about to say more, breathless as a new, possibly mad, desire seized her. The Phantom raised one finger to quiet her.

"Erik," he spoke softly

"Erik," she shivered as she spoke his name. "I wish for a mask."

The Phantom, Erik, paused. Frozen?

"Christine, you do not need to hide," as he spoke, he softly caressed her scars.

"That's not why," voice melancholy, "It's so that I may understand you."

"Understand…" Erik hesitated. This was one thing he had never yet experienced; Christine had taught him many things. He was never sure how to behave around her, she was the source of so many new memories, new feelings… How to respond?

Christine lifted her own hands, gently resting them on Erik's head, one softly pressed on his hair, the other cupping his cheek. She paused; a small movement could take his mask off, yet she knew the anger which lurked under his tranquil expression, should she do that against his will.

An almost-tense nod from the Angel of Music. Christine slowly took the mask, exposing his face to the air; she didn't even blink at the features which repulsed so many others.

Curious as to the sensation, Christine turned the mask around, placing it on her own face, hiding those scars from the world. A smile; one hand still holding the white up.

They kissed again, roles now reversed. Christine concealed her face behind the featureless mask; Erik was open to the world.

And there was no more to be said or sung.