It was a beautiful sunny day and Severus Snape was walking with Lily Evans across the grounds at Hogwarts. Most of the other students were sun bathing by the lake, and these two were alone walking towards the school court yard.
"Severus, I can't believe how naïve you're being. You still think that you can become a Death Eater and be my friend at the same time. Even if you were to take for granted that I would still want to be your friend, you can't possibly think that they would allow it. That he would allow it."
They stopped and Lily leaned against a stone pillar and looked into his eyes. He looked at her pleadingly. "Lily, I would never let them hurt you."
"See, that's what I mean! Do you even know what you're saying? I may not be an expert on the matter, but everyone knows that once you join You-Know-Who, you have to give yourself to him completely. If he asked you to torture me or kill me, you couldn't refuse!"
"I would never - !"
She shook her head sadly and looked down. "Sev, I know you wouldn't want to, but I also know you're not stupid enough to think you would have that choice. I keep telling myself that you don't understand what you are getting yourself into, but my friends all say that I'm blind and that really you have made your choice, and its for them. The Death Eaters. Its true though, isn't it? When it comes down to it, you know you can only have one or the other, and you've chosen that life."
She looked back up at him. He spluttered, looking for the right words. He knew it would be difficult to protect her if they were just friends, but he had always planned to be with her. She would be his wife, they would have a family. And he would be the Dark Lord's most trusted servant, he would never put a foot out of line, and the Dark Lord would not harm his family.
But he knew he couldn't say any of this. "The Dark Lord would have no reason to go after you, Lily. You're not a threat. You would just have to keep a low profile -"
Suddenly she looked very angry. "And what if I want to be an Auror, Severus? What if I decide that I want to spend the rest of my life hunting down people like you?"
She spat out the last few words, and he looked so heart broken that for a moment she felt guilty. But she had to be honest with him. She had promised herself that this would be the last of it, she would make him choose, and she already knew what he was going to do. She just owed it to their friendship to give him the chance to change his mind.
"Lily, please. You can't fight him, you can't win…"
"Severus, I don't know if I'm going to be an Auror. I don't know what I want to do when I leave school yet. But I do know that I will do everything in my power to stand up to He-Who-Must-Not-Be-Named. Even if it costs me my life. Because it's the right thing to do, Severus. Why can't you see that?"
"Please, Lily, don't make me choose. This is the only thing I can do, I'm meant for this life, it calls to me…"
Tears welled up in her eyes. "I'm sorry to hear that, Severus. I'm sorry you think that you aren't good enough for anything better than being a slave to the most evil wizard alive. But if that's your decision, I'm not going to waste any more of my time trying to talk to you out of it. Goodbye, Severus."
She pushed past him and started to walk away. He reached out and put his hand on her shoulder, and she took it in hers and kissed it. Then she let go, and walked into the building without looking back. She didn't want him to see her crying.
She didn't talk to him or even make eye contact with him for the rest of term.