Harry's eyes popped open as the dizzying array of colors wound through his mind. Was he never going to get used to the sensation of memories flooding back to where they belonged? It only happened every single night. He silently pulled on a dressing gown and padded down the stairs in bare feet to the common room.

The red and gold tapestries on the walls seemed to almost glow in the light from the dancing flames in the fireplace. Neville's head and shoulders were silhouetted against the flames on the couch as he leaned forward, his elbows on his thighs, chin resting on his fists, staring into the flames as though lost in thought. He didn't turn or move when Harry sat down next to him.

"Evening," Harry said in a low voice, pulling out his wand. "Muffliato."

Neville's eyes didn't leave the fire. He chewed on his lip.

"Neville, what's bothering you?" Harry asked. Neville's eyes flicked to Harry for a moment before returning to their contemplation of the flames, and Harry thought he wasn't going to respond.

"I've puzzled out the timelines," was all he said. Harry just then noticed the flask with its dancing lights in the pocket of Neville's robe.

"Isn't that a good thing?" Harry asked slowly. "You look like the world's fallen apart."

"It did," Neville responded in an empty voice, his eyes staring into some point hundreds of miles within the fire. With a heavy sigh he wrenched his gaze from the fire and turned his head to face Harry, who was shocked to see how bloodshot Neville's eyes were. Had he been crying? How long had he been down here?

Before Harry could ask, Neville stood, pulled the flask out of his pocket and unstoppered it. The small window of the timeline that was their current residency - sometime in their sixth year - floated out and hung in the air, but Neville used his wand to coax the rest of the lines from the flask as well. They settled in the air like bright razor-thin cobwebs, circling the room several times, the dark green almost invisible in the low light.

Neville jabbed a finger at the white timelines near the end, before they began to fray. "This," he said hollowly. "Right here. It's yours."

"Right," Harry said, standing to study it. He swallowed. "It's where...where Lily dies."

Neville shook his head violently, his hand shaking slightly. "No. She's killed." He closed his eyes, as though the expression of shock on Harry's face pained him. Maybe it did. "Ginny kills her."

Harry didn't realize he had sat down heavily. "No," he said emphatically. "She doesn't. That's not...it's not possible. No."

"It's right here, plain as day," Neville said tonelessly, his eyes still closed. "Except you're right, it's not Ginny. She's possessed." He opened his eyes and traced a line Harry had never seen before, perhaps because it was so faint next to the bright white lines. "This here. It takes her around the same time you were confronting that necromancer in Bath." He traced it from Ginny's line back to its origination. "The necromancer in Bath was a decoy, the apprentice, to take you away from Ginny for long enough for the true necromancer, the master, to raise this shade and give it what it needed to possess your wife."

Harry felt frozen, breathing shallowly as if a deep breath would shatter him. Neville continued in his flat tone.

"The shade needed Ginny in particular, you see, because she was already vulnerable to him. He'd possessed her once before."

Harry felt as though he'd been doused in ice water. He took a shaky breath. Now he saw what was so fascinating about the fire; it provided something on which to focus so he could pretend he was not hearing these words.

"You were after the wrong necromancer. By the time you got home, Voldemort's shade was so deeply intrenched he was undetectable. He waited, biding his time, and as soon as his hold was absolute, he made her kill Lily." Neville wiped tears from his eyes with the cuff of his dressing gown. "And then, here," he said, his hand shaking, "You confront her. It's clear it wasn't an accident. But you didn't figure out she was possessed." His voice was shaking, now. "I don't think you mean to kill her," he said, almost in a whisper. "But..."

Harry very, very slowly lowered his face into his hands.

"And then," Neville said, drawing a deep breath as though about to dive, "You...you go mad. With grief. With guilt. Whatever. And you start...experimenting. Experimenting with time. You try to figure out how to make it all never have happened, to go back and find the right necromancer, but you..."

"I cause it," Harry found himself saying. "I make Time fall apart."

Neville nodded, his hand finally falling limply to his side.

The fire popped, sending a shower of sparks up the chimney. The white lights floated, not wavering in the draft that caused the fire to sputter.

"But we're stopping it," Harry said suddenly. "That's why we're here. We do change it. We do make it so it never happens." He stood up and looked wildly for his line in the green timeline.

"We do," Neville said simply.

"So...so that's good," Harry said desperately. "I get the right necromancer. Ginny doesn't...Lily doesn't die, and I don't..."

"You don't get the right necromancer."

The words seemed almost heavy.

"What?"

Neville swallowed, eyes closed, then traced the green line. "The next steps we take reverses all the damage that happens once and for all. It reverses because what we do in the next few steps means you never marry Ginny."

"I never...but..."

"You have James by her, but you never marry her. Another Auror gets wind of the master necromancer and what he's done, but too late to save Ginny. She's killed in the crossfire, years before the time when she'd kill Lily, if Lily had ever been born. James is sent to be raised by us."

Harry pressed his palms over his eyes, breathing raggedly. The room seemed to be spinning. "This is the sacrifice I have to make?" he demanded of no one. "I either destroy the world, or save it but never have my little girl, never have my family?"

"You will have a family," Neville pointed out. "Me and James."

"You and..." Something clicked into place in Harry's mind then, and he slowly brought his hands away from his face and looked at Neville, who met his gaze evenly. "What exactly do you mean by that?"

"Please," Neville said. "You're not an idiot, Harry. You know perfectly well that the decision that we were just going to be friends was fiction. You know what's been building for the last several years."

"Can't say that I do, actually," Harry said in a dangerous tone. Neville made an exasperated sound.

"Don't be daft! You can't ignore what's right in front of you!"

"And where exactly do you see this?" Harry asked in a voice dripping with venom. "Your precious lines?"

"I'm not blind!" Neville retorted. "And, contrary to popular belief, I'm not a bleeding moron! I see it in your eyes every time you look at me, and what's more, I feel it right about here -" he thumped a fist into his chest - "every time I look at you! You and I both know how we're going to end up, even without bloody timelines!"

"You just want it to happen," Harry accused in a horrible voice he wasn't entirely sure was his. "You're using this teenaged drama to kickstart your ridiculous infatuation and you just want something to come of it -"

Neville brought both fists down on the back of the couch, his face contorted with rage. "GOD FUCKING DAMMIT, HARRY!" he bellowed. "YOU THINK YOU'RE THE ONLY ONE MAKING A SACRIFICE? I LOSE MY FAMILY TOO! I LOSE EVERY. SINGLE. ONE OF THEM, AND I DON'T EVEN GET TO HAVE ONE OF THEM BACK WHEN WE FIX THE DAMN THING!"

Yells of sleepy surprise sounded from the dormitories; apparently the limits of Muffliato's effectiveness had been reached. Harry looked at Neville with a mixture of anger and confusion before turning and stalking back up to the dormitory, shouldering past the other curious students who had emerged into the stairwell to see what was going on.

He lay fuming behind the curtains of his four-poster, not exactly knowing why. A small part of his mind observed that it was easier to be angry with Neville than to contemplate the horror of what would have been his future; he quashed it and balled his fists in his blankets. He could not wait for the morning to wipe the memories away again so he could just be sixteen with nothing to worry about but homework and Death Eaters. He already knew he could handle those.

Harry spun, his eyes wildly taking in the surroundings that hadn't grown around him, but were simply there. The hideous gold-striped wallpaper Ginny had insisted upon, the sage green rug with the white scrollwork, the oak frames on the family photos on the wall...

He was home.

Something very like relief flooded his chest and he felt like laughing. He leaned over the bannister of the landing to take in the several floors of his home, delighting in the familiarity of it. He was three floors up on the landing, which meant he was outside Lily's room. Light flooded in through the windows, casting striped shadows across -

He paused. He was standing behind the bannister, but the shadows were going right through him to the carpet below and behind him, and he did not cast a shadow himself. He traced a finger through some dust on one of the picture frames, and it left no trail. Perplexed, he studied the glass in front of the picture more closely, then a glint of red and gold caught his eye in the photograph and he changed his focus to the photograph himself.

It was of James, that much was clear, and the glint had been the sun reflecting off the Head Boy badge that he was displaying proudly on his chest. Harry's mouth dropped. James was only in his fourth year, he couldn't possibly...

Of course. This wasn't his time. And the photograph seemed to suggest it was the future, his future. In fact, he realized further, dust motes in the air, suspended in the sunbeams, were not moving lazily with the air currents. Carpet fibers were not bending beneath his feet. It would appear that not only was he glimpsing his future, he was in a very specific frozen moment in time as well. He couldn't directly affect anything here. Thus he couldn't cast a shadow, nor move dust on a picture.

Lily's door down the hallway was ajar. Something sent a spike of apprehension through his chest, and he licked his lips and began to slowly walk down the hall.

The door was not open very far, only a few inches. Harry tried to push it open more but it resisted as solidly as if it had been a stone wall. He angled himself to look through -

He was not able to stop the cry of anguish that erupted from his throat.

Lily was crouched at the foot of her bed, hands pressed to her throat, red seeping through her fingers, an expression of horror and pain marring her features. Blood was already spattered on her lavender carpet and white bedspread, a handprint on one of the bed's posts testament to a failed effort to pull herself to standing. Her eyes were tight with pain, her mouth open in what was unmistakably a scream. And to the far edge, mostly obscured by the door, the end of a wand could be seen, a wand Harry would recognize anywhere as his wife's.

"Oh, god," Harry gasped, stumbling backward, his hand over his mouth. "Oh god, no..." His heart pounded in his chest, adrenaline making his mouth taste bitter and metallic. A great weight settled on his chest, and he struggled to breathe. He dared not blink, for closing his eyes brought up the ghastly image again...

"I am sorry you had to see this," a familiar voice said from the staircase.

Harry spun, breathing heavily, to face Dumbledore, who spread his hands in a helpless gesture.

"Why?" Harry choked. His eyes darted back to the door and he wrenched them away, lest he accidentally see the scene again.

"Because you have reached that cusp where a decision must be made," Dumbledore said sadly. "Do you go on and prevent this from happening, but never see your daughter or youngest son born nor marry your wife, or do you stop and know that in a few years, you will once again stumble upon this scene, knowing that you could have prevented it - but still having those precious few years of time before it happens?"

Tears burned Harry's eyes and he shook his head. "I can't," he said thickly, "I can't make a choice like that, I can't..."

"Then let us go forward further," Dumbledore said. "Do you go on and prevent Time from collapsing, or do you cause it to pause in perpetuity?"

"STOP!" Harry begged, sliding on his back down the wall and hugging his knees to his chest.

"You must decide," Dumbledore said heartlessly. Harry lifted his eyes, and a glimmer of understanding lit in his mind.

"You're not Dumbledore," he said hoarsely.

The figure that wasn't Dumbledore bowed his head. "It seemed prudent to appear to you in a form you would trust," it said.

"I won't like what you say no matter how you appear," Harry proclaimed. "You may as well show yourself as you are."

"You don't want me to do that. However, this may cause you less distress." There was no change from one form to the next; one moment Dumbledore stood before him, and the next, a vaguely humanoid form made of diamond bright light.

"Why show me this?" Harry demanded, gesturing toward Lily's bedroom door. "Are you mad?"

"I show you because you need to fully understand the decision you must make," the being that could only be Time said in an ethereal voice. "I need you to comprehend what each branch of decisions will lead to. Neville already understands, and he has made his choice. You, however, are a torrent of painful indecision that eats you from the inside, and the longer you do not choose, the harder it will be to make a choice, until I cannot continue either way."

"I lose Lily no matter what I choose," Harry choked out. "And Ginny."

"You speak correctly," Time said. "You also will never know the grandchildren Albus would have had, if I had been allowed to continue past your meddling. That is something you will never know, Harry Potter, and by your own hand, should you choose one branch."

A sob broke free of Harry's chest and he touched his forehead to his knees. "And if I choose the other?"

"James grows up without a mother, but still knows what it is to have a loving family. You never have a daughter or second son. But you know peace, as much as mortals can know peace. What is more, I continue." The figure made a gesture that could almost be a shrug. "It matters not to me which path you choose. I exist outside your linear concept, and cannot ever begin or end. Beginnings and endings are the workings of a mortal mind."

Harry closed his eyes. "Why can't I change this?" he asked plaintively. "I've changed so many other things, big things...why can't I stop this?"

"Because this has nothing to do with your actions. All else was able to be changed because the events unfolded as they would have, as they should have, had one single event happened as it should. The 'big things' you have changed started with a single small thing, building momentum. There is no such small thing that will both prevent this and preserve your life as you know it."

Harry swallowed. "Do I have to decide now?"

"You may stay within this construct until you have made your decision, but a decision must be made before you can proceed."

Harry quailed. "It has to be this place? With...that?" He jerked his head toward the door.

And he was suddenly sitting in his chair, in his office at the Ministry of Magic. Parchment was stacked in neat piles upon the desk, and several memos were frozen in midair above his head.

"You have made many difficult decisions in this locale," Time's voice registered from nowhere. "Is it more fitting?"

"Yes," Harry said with profound gratitude. "Thank you."

"You may take all the time you need."

Harry glanced around. "How do I let you know when I've chosen?"

"You needn't. I will know."

And even though Time hadn't actually been there, he somehow knew he was alone.

He propped his elbows on the desk and lowered his face into his hands, willing the tears in his eyes to go back to where they came from.

Logically, he knew exactly what he had to do. Logically, there was no argument. And yet, committing himself to that was harder than anything he'd ever had to do. Having made the decision in the past, he knew for a fact that choosing to die so that others could live was a much easier decision than the one he made now.

It was unfair to say he had a favorite child, but very apt; he doted on Lily outrageously. His daughter, his beautiful little girl - not so little anymore, of course, but his little girl all the same - how could he never know her? What was more, how could he choose to create a reality in which she simply did not exist, even if the alternative was -

Then, it struck him, so clearly that he was amazed it had not occurred to him earlier.

He never, ever wanted to see Lily like that again, never wanted her to ever know that kind of pain and terror, and no price was too high to ensure that.

His heart heavy, but steeled with determination, Harry picked up the family photo he kept on his desk. Ginny, Lily, James, Albus, and himself smiled and waved up at him.

"I love you so much," he told his children and wife, his voice breaking on the last word. "All of you." His hand began to shake and he closed his eyes tightly and clenched his jaw, tears running down his cheeks. He swallowed. "Goodbye."

He opened his eyes, and was not surprised to find himself seated on the edge of his bed in the dormitory, across from Neville, sitting in a mirror image to him. Neville opened his mouth as though to ask a question, but nothing came out.

Harry nodded, once, then reached out a shaking hand. Neville grasped it with both of his, and the look they exchanged spoke more than words ever could. It spoke of terrible loss, of unspeakable sacrifice, of sorrow and despair - but also of a tiny glimmer of hope for a new future, an echo of anticipation, and, yes, a shadow of satisfaction.

The last thing Harry saw before the brilliant white light became too bright was Neville's eyes.