"We'll work on your pathetic inability to lie convincingly another time, Gryffindor. Ask your questions."
"It's called civility," Harry retorted, his stomach finally calming. "You didn't want to talk about it, remember? I'm trying to respect that."
"So you can lie convincingly?" Snape mocked.
It was on the tip of Harry's tongue to say Sod off, Snape, but he thought he'd better not. "Where did Remus go for that ice cream?" he said instead. "All the way to Diagon Alley?"
"Stop procrastinating and ask your bloody questions!"
"Okay, okay." Harry held up his hands as though to ward off Snape's rudeness. "Since you insist. How come Voldemort let you just stand there and watch? I mean, every other Death Eater there, he told them what to do and they did it." A low shudder coursed though his shoulders at the thought of just what the Death Eaters had done.
"Every other Death Eater?" Snape mocked.
"Turn of phrase," Harry excused it. "Don't pretend you didn't understand me. I know you did."
Snape curled a lip. "You must be feeling better, you insolent brat."
"Be glad I trust you enough to be insolent," Harry snapped. "I'm not stupid, you know, whatever you like to call me. I wouldn't speak my mind around you if I didn't feel safe doing it."
"That explains a great deal," Snape retorted, nostrils flaring. "I suppose I can understand what makes you so horrendously rude to Lupin, in that case. You must feel extraordinarily safe with him."
"Yeah, well, I do. So what about my question?"
"Ah yes, the Dark Lord." Snape sat up straighter in his chair and conjured a cup of tea for himself as he assembled his words. "He trusts no one else to make his potions, Mr Potter, and contrary to what you might think, not all the elixirs he needs are strictly Dark Arts. Many consist of what the uninformed tend to term 'Light Magic.'" He paused to sip his tea. "I convinced the Dark Lord years ago, during his first reign of terror in fact, that the preparation of certain elixirs requires my hands to be clean of blood."
"How'd you convince him of that?" Harry had to ask. Compared to Snape, he didn't know much about potion-making, but he knew enough to recognise a cock-and-bull story when he heard one.
"My position as the foremost Potions Master in Britain helped," Snape informed him, nose lifted a bit. "Add to this the fact that many of the elixirs I refer to are my own development. No one else can make them, thus the Dark Lord is in no position to dispute me when I tell him what such potions require."
"And you're good at Occlumency, lies, and misdirection," Harry added.
Snape sneered down his long nose. "You think matters are so simple, Mr Potter? I don't break under Cruciatus; that's the main reason the Dark Lord believes my claims. He summoned me every night for a week and cursed me as thoroughly as his powers would allow. And when I still insisted that I could not have blood on my hands, then he finally let me be."
"Cruciatus every night for a week?" Harry gasped, closing his eyes. He remembered the Longbottoms, tortured with the curse until they lost their minds, and realised with some measure of respect that Snape was far stronger than he'd ever given him credit for.
"I, however, was not fourteen," Snape admitted, his eyes a bit shadowed at the memories.
Harry cleared his throat. "Um, well . . . how come you didn't tell him, while you were at it, that you couldn't watch things like that, either?"
"A spy is not much use unless he has a chance to be present," Snape dryly explained. "Who can say what the Dark Lord might reveal of his plans and intentions during one of these . . . sessions? He finds them recreational, did your poor pure Gryffindor brain not glean that much from what you saw?"
"Yeah, I got that," Harry answered, deciding to ignore Snape's phrasing.
"He is more likely to let things slip over his tongue when he is relaxed," Snape said with some measure of disgust. "It was during a raid on Muggles that he revealed his plan to capture a certain prophecy, for example. I have to be there to hear such things."
Harry swallowed, nodding. "But . . ." Tears rose to his eyes, though he didn't let Snape see. "But don't you wish that you could stop it, save them?"
"I don't wish anything," Snape flatly denied, his eyes hard. "I can't afford to. I Occlude my mind, and layer my thoughts so that he sees nothing but bloodlust, and rage, and deep-seated regret that I can't partake as the others can."
"How do you make yourself feel things like that, things you really don't feel at all?" Harry whispered, appalled.
Snape's lips twisted into an expression of self-loathing. "I have a memory, Mr Potter. Unlike you, I know how to use it."
"You mean you used to like seeing people being tormented and torn apart?"
"You oversimplify everything, which, I might add, is one of your major failings in Potions class," Snape mocked. "Shall I explain it in terms even you can comprehend? Once upon a time, I was an angry young man. The Dark Lord used that. And before you decide, in your Gryffindor nobility, to somehow idealize me as just one more of his victims, allow me to share another shard of truth. I fully agreed with his views on blood purity." He snapped his fingers, the sound almost explosive, it was so abrupt. "I would not have thought twice about killing your mother, and even less than that about killing you."
Harry was quiet for a long moment, before he asked, "What changed?"
Snape scowled. "I found I could not agree with executing blood traitors, as the Dark Lord called them. Any fool could see that there were too few purebloods as it was."
Harry didn't like the sound of that. "That's it?" he quietly questioned.
"At first, yes. But it led me to other questions, other conclusions." Snape sighed, and leaned his chin on his hands as he sat at the table, his dark eyes turbulent. "I began investigating bloodlines and discovered to my dismay that everything I had believed about wizardkind was founded on entirely false suppositions. There are no purebloods, not in the sense I once thought. We all have Muggle heritage; yours is simply more proximate than mine. And to say that only wizards are fully human is a complete misrepresentation of reality. We are the ones with non-human ancestors; it's where the magic comes from."
"I just knew Malfoy was part veela," Harry weakly joked, biting back on the other part he wanted to add, that Snape was likely part vampire.
"A hundred generations back, or more," Snape merely commented. "It's why Muggleborns exist, in fact. The magic mated into the bloodline finds full expression at some point in time. Pure-bloodedness is a myth. You are no less a full wizard than I, and your mother was every bit a witch."
"But about the Death Eater meeting . . ." Harry gestured hopelessly with his hands, trying to communicate regret that he still didn't understand. "Afterwards . . . when you get back to your dungeons, when you're free to really think, don't you wish then that you could have saved them?"
Snape suddenly shoved his chair back as he stood. "I can't save them. It's not in my power. I stand there with twelve, sometimes twenty, Death Eaters, every one of them intent on worse than murder. If I make a move to save anyone," he sneered, "it will not succeed. I will have sacrificed my only advantage for nothing!"
"I know you can't save them, Professor," Harry murmured, his words washing over Snape's obvious pain. Pain the Potions Master was trying to deny, he recognised. "I'm sorry you have to see those things, time after time, and even sorrier that I asked you about them. You're a brave man."