The Curse
Disclaimer: I don't own any of it. J.K Rowling does.
"Severus….. Please……" Albus Dumbledore was barely able to speak. But Severus Snape knew what he was begging for, and couldn't do it. Not really. But he knew of something he could do, which would make people think he had done it. A Time-Travel curse was just a few shades paler than the sickly green of Avada. Not enough difference for anyone who wasn't intimately acquainted with the two spells.
Severus cast it, wincing as the body of his friend was thrown backwards over the side of the tower. "Good luck, Albus. Come back to us safely. I love you." The younger wizard had murmured, before stowing his wand and running as fast as he could. He had to get as far away as possible, before people knew what he had done, what he hadn't done, and what he was. If they discovered that he was a Death Eater, his life was forfeit. He wished it were already. He didn't know how he could live with what he had been forced to do.
"Forgive me, Minna. I couldn't do anything else. At least we'll see him again, I hope." He pleaded, silently. Minerva McGonagall lifted her head for a second, stared almost blankly ahead into the room, and then whispered, "Take care, Sev. Good luck, Daddy," before starting to rock, crying hard. Even the knowledge that she would see her adopted father again was of no comfort to the elderly witch, not with the knowledge of what had happened, and of the fact that she now had to be the one to attempt to guide the children, when all she wanted was to be a kid again herself.
And meanwhile, Harry Potter was staring in silent horror. He had just watched his most hated professor murder his most loved professor. Sure, his feelings towards Dumbledore were changing, a little, but as Dumbledore became more open with him, as they started to see each other more as equals, as Dumbledore started to challenge him, and to make him think for himself, and to test what he could do, as Dumbledore gave him more trust and responsibility, Harry realised that nothing, even the mistakes he had previously thought unforgivable on the part of his headmaster, couldn't be changed, couldn't be made better. There was nothing they couldn't recover from, if they worked together.
Of course, he hadn't counted on this happening. Dumbledore being murdered just wasn't something Harry had considered possible. Albus Dumbledore was invincible, getting murdered just didn't happen to the Greatest Wizard Who Ever Lived-Bar Merlin. It just didn't. Harry couldn't believe—didn't want to believe—that Albus was dead. It just couldn't be true. He grabbed hold of the broomstick he had flown up on, and straddling it, performed an almost free fall dive off the tower, landing beside the prone body of his headmaster. "Professor! Professor! Professor Dumbledore, wake up! You can't be dead, you have to help me fight Voldemort, you have to help me find them and destroy them! You can't be dead! You can't leave me! I need you!" Harry was babbling, sobbing. He could not, would not believe what he had seen. He just wouldn't. It just couldn't be real. He needed Albus, the world needed Albus, Albus couldn't be dead; it just wasn't possible. "Please, Professor, I need you. You can't leave me. I'm lost and scared, and I don't know what to do." Harry sobbed, finally collapsing next to the broken body of his headmaster, wrapping one arm around the older wizard's once-strong shoulders. "Please, sir. Please." Harry had never felt more helpless, more alone, than he did right now, and considering his history with the Dursleys that was seriously saying something.