In reality, what happened next lasted about five minutes. For Severus it seemed to take even less time.

"This is it, Severus. We cannot wait any longer. I'm going to cast the spell and I'm counting on you to do as I asked. You'll know as soon as I've transferred the Horcrux. Do not wait for anything. Cast the spell." Dumbledore's blue eyes locked piercingly on Severus' as he held the younger man's arm firmly. The grip was too tight, almost painful, but Severus was glad for it. He feared that if Albus were to let go he'd crumble.

He thought he'd have more time. He couldn't do this.

"You can." Albus seemed to be reading his mind. His other hand landed on Severus' shoulder, squeezing comfortingly. "You will."

A strangled cry pierced through the air, breaking the moment.

Remus wasn't quite sure what happened. One second he was shaking Harry, begging him to breathe. The still chest heaved and Remus felt his own lungs take in a much needed breath.

"Thank God."

The next thing he knew, he found his head bashed against the foot of the bed and thin, bony hands were wrapping around his neck and squeezing. He grabbed at the hands around his windpipe, trying to pull them off, but the more Remus struggled, the more his air was cut off. He was flung to the side by inhuman strength, and then Harry was straddling him. Red eyes blazed down.

In a daze, Remus struggled harder. He was vaguely aware of Poppy shouting as his vision began to grow dim. He felt himself fading. White was crowding in on his vision.

He couldn't die like this; at the hands of his best friends' son. The last bit of air left him.

Out of instinct, Remus tried to inhale and surprised himself when a cool wisp of air found its way in. He greedily took another breath, then another as he began to cough harshly. His vision stopped tunneling in and the world came back into focus.

Severus had his arms around Harry's torso and was pulling hard. Poppy had her hands around Harry's and was prying them from the death grip he'd had around Remus' throat.

Remus found himself freed and he scuttled backwards as Severus lifted Harry off him. The werewolf's hands went to his throat, almost able to sense the bruises that were already starting to purple there. He felt blood from where Harry's nails had pierced his skin and gasped heavily, savoring the ability to breathe.

Albus' voice rung out over his head and Remus looked up. Severus was still holding Harry tightly against his chest as Albus towered over them. The boy fought against the hold but the longer Albus spoke, the more energy Harry seemed to lose. The words sounded familiar to Remus, but he didn't understand them. It seemed to be a chant of some sort, and Remus found himself growing hypnotized. A dark red strand of light wove its way between the headmaster and the struggling boy.

The weaker Harry became, the stronger the light seemed until Harry slumped motionless in Severus' arms, and the light went out. There was dead silence for a second until the red light burst forward again, as if from a wand, and shot straight into Albus. The old man was sent stumbling backwards.

Severus froze in place. This was it, the moment he had been dreading. The body in his arms grew lighter as the burden of what he had to do grew heavier in his chest.

The Headmaster regained his footing. Severus sought out his gaze, hoping that something had gone wrong, for the spell not to have worked. But there was no twinkle waiting for him in that blue gaze. The old eyes had already begun to be tinged red. Among the rage that seemed to have taken over, Albus' eyes bore a look of pleading, searing straight into Severus' heart.

"You made a promise to me…"

This was it. Dumbledore reached for his wand. Severus let go of the burden he was holding, allowing the limp body to fall to the floor as he grabbed for his. The curse was on his lips before anyone, let alone himself, could register what was happening.

"Avada Kedavra!"

A flash of green light, and it was all over. Albus Dumbledore crumpled to the floor, long white hair fanning out framing his pale face. Severus moved forward to stand over the old man, raising his wand to cast the spell again. The old wizard's eyes were still open a crack; no more red.

Ignoring Poppy's sobbing and Remus' astonished gasp, Severus held his wand tightly, forming the unforgivable words once more. His vision zeroed in and Severus tried to banish all thoughts from his mind.

"Avada –" Dumbledore's eyes flickered. Severus felt the words catch in his throat. His thoughts were a whirlwind right now. He had to cast the curse again; there was no choice in the matter. Severus stared down at the Headmaster.

This was Albus Dumbledore, the greatest wizard of all time. The old man lay at his feet, at his mercy. Severus had a job to do. He attempted to focus on his task. Years of being a Death Eater had honed his skills at disconnecting from the situation, allowing him to perform as needed, but it wasn't working now. This wasn't just another wizard, this was his mentor. Memories of hard times raced through his head, times when Severus thought the world was ending, when he thought there was no hope and Albus Dumbledore found his way through the fog, pulling Severus back from the edge.

His wand clattered to the floor besides the prone Headmaster. He couldn't do it. This was Albus Dumbledore. Severus couldn't do it. Feelings of failure and guilt pooled inside him and Severus collapsed on the floor next to his wand.

"I can't, Albus, I'm sorry." His whispered voice came out sounding tortured, and indeed that's what Severus felt. His insides churned at the thought that he couldn't give Albus what he asked for. To kill the person that had given him his life back…Severus couldn't; he wouldn't.

Dumbledore's eyes flickered again and Severus felt his composure rushing back. He straightened up, shoving his wand back into its holster.

"I'm sorry, Albus." And as the blue eyes focused on him, Severus bowed his head, unable to face the disappointment in them.

"Severus." The charred, black hand took hold of his own and tugged. Severus kept his eyes averted. "Look at me. I'm asking you, look at me."

Slowly, Severus returned his gaze to the Headmaster. "Will you not do what I asked, child?" His voice was low and somber. Severus felt guilt upon guilt teasing its way into his chest. He shook his head.

"Please...do not make me do this."

A peaceful look settled over the old man's face, leaving Severus confused. "Then promise me that you will keep your oath to protect him. Protect Lily's son."

"Albus-"

The grip on his hand became a tight pinch and Albus' voice was harsh. "Promise me!"

Severus nodded sharply. "I promise."

His grip slackened and Severus' arm was released. A 'whoosh' sounded and Albus looked past him towards the fireplace. Severus' eyes followed, resting on who had just come through the floo.

"Healer Dalton."

Albus' voice was soft again as he watched her take in the sight of the damaged room.

"It's Lailie, Headmaster." She rushed over to them as Severus sat there, distraught over his inability to perform a task he had been commanded.

"Very well, Lailie. Then I must request the same courtesy."

"Of course, Albus."

"Lailie, I need you to finish it."

Severus' head shot up. He barely registered Lailie nodding. Her arm raised, wand in hand. Severus rocked back on his heels, a groan emitting from deep in his chest as that sharp jet of green light slammed into the old body, causing it to go slack. His arms shot out, grabbing Lailie sharply.

"What have you done?" It was a vicious hiss that escaped his throat as he shook her. "What have you done!"

She did not try to pull away, just sat there as he yelled over and over again. Tears he did not know he could shed slipped from the corner of his eyes as he grieved for his departed mentor.

"He asked me. He knew he asked you for something you were incapable of." She spoke softly, almost as if he were a child. "It was the only way to make sure the plan worked. Albus and I both knew it. You knew it too, Severus."

Despite his despair, Severus nodded. It was the only way. Albus had explained that to him. His thoughts drifted a bit, remembering the last conversation he had had with the old man. A sniffle brought him back to the present moment and unease drifted over Severus as he realized he had to explain the last few minutes to the other two in the room.

Lailie seemed to sense his discomfort and placed a hand on his shoulder, which Severus tensed under. "I'll explain it to them. You deal with Harry."

Potter. Damn it. Severus had almost forgotten about the boy. He glanced besides him, but there was no body lying next to him.

"Here, Severus." Poppy called over gently, her voice cracking as she held back more tears. Remus was next to her, leaning over the bed they had placed Harry upon. Severus stood quickly, regaining composure.

"How is he?"

Poppy shook her head. "The fever...what can I do?"

Severus reached out, placing a hand on the fevered brow. Pulling the potion vial out of his robe, he uncorked it and placed it against Potter's mouth, lifting his head so that he wouldn't choke. "The antidote to the binding potion. Albus and I–" he fumbled over the words. He felt their skepticism and shock over what had happened sweeping off them. "Potter's life force is entirely attached to his power. By binding one, we bound the other." He placed the empty vial on the nightstand and reached for the skinny wrist, glancing at his watch at the same time. "He was fighting for his life in more ways than one."

"Will he be alright now?" Remus' voice was surprisingly steady as he moved a little closer to the bed.

Severus waited a minute before answering. "His pulse is slowing down, and his skin is cooling off." He looked to Poppy who nodded after testing the boy's pulse herself.

"Will he wake soon?"

Very uncharacteristic of herself, Poppy shrugged. "We'll have to wait and see." Slowly, she began moving around the bed, casting diagnostic spells at the still figure. "It might be a long wait."

Severus felt himself snort. It's been such a long night already. He turned and walked down the wing, heading towards the fireplace. Lailie had moved the Headmaster's body onto a bed, and as Severus walked passed, he felt the need to stop. He turned around and gazed back at Potter's bed.

Poppy was still casting spells and Lupin had settled himself in a nearby bed, obviously intending to stay the night. He looked back at the body covered with a sheet, and then once more at the battered child across the room. Severus felt something tug deep in his chest as his gaze traveled between the two.

How could you do this to me, Albus. How could you leave me? Why trade your life for his? How am I to protect him? He is just a child...so weak and fragile...

A heavy sigh shuddered through his body as he turned again to leave.

Protect Lily's son

Severus turned back once more. He gingerly walked over to Potter's bedside, and conjuring a chair, sat himself down.

Poppy was right. It was going to be a long wait.