Disclaimer: I don't own anything except the plot. Maybe the original character or two I throw in, but that is it!
What it?
Severus Snape was the best potions master Hogwarts had, but truth be told, he was overly modest on the subject. He only wanted to teach Defense against the Dark Arts, which she had been planning on teaching, and he wanted to fulfill her dream. But of course, he couldn't. Dumbledore wouldn't let him for some reason. So what was the use in teaching? It was her dream, and he wanted to live it for her, since she wasn't living anymore. He had grown to enjoy teaching, but he still missed her. His hair was a mess, but he only did that to smite her. She couldn't force him to wash it anymore. His hair used to be longer too. He'd been teaching for 14 years, and it seemed like forever since she left. Remus and Sirius had missed her as well, but neither of them talked about it anymore in front of Snape. She used to be able to stop them from being enemies, but only while she was around. She was Lily's best friend, like a sister to her.
She was the reason he became a spy. To protect her, he hadn't wanted to loose her, and so he could help stop the slaughter. Besides, she was already planning to destroy the Dark Lord, she had fought him multiple times before, she had destinies with him unknown to all, even the ministry had no records of those destinies, and they believed her a traitor. He smiled at the thought; it was funny that they thought her the traitor only because of her strength. He had willingly bled for her.
She had protected him, just as much as he had for her. At the school, he remembered when he was there, she was too, and he had tried to hex and curse her and get her mad at him. She never would, she'd just smile and never tell who had cursed her or injure her. She said she didn't do that to people she cared about. He remembered how she had saved him from sickness by making it to the forest temple in time, she was the Protector of Forest, and she had saved him, cared about him enough. She dared to care about someone like him!
He was always the outcast, and yet, she always hung around, she'd try to learn hexes from him, and he, he learned how to be happy. He didn't have any good childhood memories, except with her. She wasn't eve a Slytherin, well, she was for two years, and then had permission to 'transfer' to Gryffindor (be resorted) because her powers had affected her sorting. He was always humbled around her, simply because she was wise, powerful and courageous.
She taught him how to love, how to care. She had taught him how to hope. She inspired him to try to do better, even though people such as Potter and Black tormented him. But that was only when she wasn't around. They had even battled together, a great team. They won battles, but Severus was careful not to get her in a bad mood, or else in a Quidditch game she would hit a bludger at him. He missed that.
He could never hide the truth from her, one, she was a psychic, and two, she meant something to him. She always made things equal and fain when she was around, at least, more fair for her. She was short, but not too short.
But he killed her, took her life from Snape. The Dark Lord destroyed the threads of happiness that bound him to this Earth. He had taken her life. He had cried out his love for her forever. And then he swore never to forgive Voldemort, to keep on being a spy, and to live out her dreams. Lily was crushed. At least she never had to see Lily die, but she would have loved to see Voldemort's downfall.
He went on trial of course, but nothing really came of it. He was free. She had died, died to save him. She had run in front of the spell and took it head on. It plunged through her and she bled. She bled to protect his life. She had loved him. She loved him enough to marry him, to be with him. She would do something like that. She shined a light in his darkness, and Voldemort would pay. This time the Dark Lord would die and not come back, not because of the fact he hated him, but because she might still be alive. That was his hope. It was a false hope, wasn't it? What if he had taken the blow? What if she hadn't died? What would have happened if he had protected her better? He'd love her… forever…
What if?
He broke down and cried.