Kill
Your fingers move to your neck for a moment in the shock of the bite. You stare at the tips of them, covered in the deepest red.
So this is the end. Voldemort kills his greatest spy. It does not matter that you were never on his side, for he does not know this. No one knows this. No one besides a portrait.
You put the hand against your neck again because the blood is pounding in you. You're bleeding pretty quickly. It's hard to believe you were bitten by some pet snake. No Killing Curse for you. The Dark Lord's pet snake is worth more than his spy—again, for all he knows, you may have been his most loyal supporter. And even though you were not, it all seems as if in vain. The only one who knows you is buried on Hogwarts grounds by the point of your own wand.
You knew you'd never make it through this war, so I don't know who you were kidding when you used to come up with grand plots for the future. Your own apothecary. Early retirement. Leading Hogwarts with some dignity. None of these things, you knew (You had to have known!), would ever happen.
You gave up your life when you turned spy—not that it felt much like living after the love of your life was slain. You'd tried everything to save her. Your everything was not enough.
The pain is intense, is blinding. You cannot bear it! You feel like screaming until you scare the pain away. How futile. "I regret it," your old 'master' had said to you. But he doesn't, never would have, and any first-year with half a brain can have told you that (O, if only you'd known that around two decades ago…).
Your throat is going dry and there's a roaring in your ears like the sounding of the sea. And you know very well that you are drowning, drowning in the blood spilt, in the venom percolated. Suddenly, a new figure arrives on the scene, and for a moment you see the surface of the water pressing down on you—there is hope. He throws the insufferable cloak to the ground, which is where you already lay. You grab onto the front of the boy's robes as if he might actually lift you from the depths of your demise—the demise you signed up for.
There is such pain and numbness, and they mingle inside your body in a way that frightens you. You grip harder at the fabric. "Take . . . it. . . . Take . . . it. . . ." Can't he see the effort you are making to explain things, to show him who you really are?
You can barely speak as your essence spills from your pale, black-clad neck. You push the memories away, try to purge them from your body. You have no more use for any of them. The insufferable know-it-all strikes again, coming to your rescue, handing Potter a flask. She takes your memories from you carefully, and finally you know your story will be preserved.
You loosen your grip, or rather it loosens of its own accord. You have given your last efforts to make sure they know what you really are. Who you loved, what you lost.
"Look . . . at . . . me. . . ." you whisper, and it's hoarse. The eyes of the one you loved for a quarter century are preserved in the face of her son. He looks like James. And in that moment you do not care.