The memory ended and they landed on their feet in the tower office, Harry's fists still curled in Snape's robes. The man made no move to dislodge him, at first – Harry even imagined an answering grip upon his shoulder – but when it was plain that Harry would not release him of his own volition, Snape cleared his throat, rather pointedly, above Harry's head.

“Sorry, sir,” Harry mumbled, pulling away and swiping a sleeve across his eyes. Outside the horrors of the cave, it suddenly seemed rather foolish to cling so to the man's robes.

“It is unnecessary,” said Snape.

“Yeah, I know – sorry.” A dull flush crept up the back of Harry's neck.

“I meant your apology,” said Snape.

Harry glanced up at him, and saw that rather than his usual smirk, the man's face bore an expression of slight discomfort, which was itself overshadowed by his almost deathly pallor. Harry looked away – he rather wished that the ground would, in that moment, swallow him up – and whispered, “Thanks.”

“That, too, is unnecessary.” Snape coughed again, and said, “Perhaps you do not understand the import of these events, Potter.”

“What do you mean?”

Snape favored him with a small smile – not a smirk this time, or a sneer, but rather a look of weary but genuine amusement. “We are allies, now, are we not?”

Harry thought about it a moment, his brow wrinkling behind the frame of his glasses. “I... guess so.” More surely, he added, “I don't think you killed him for Voldemort anymore, or anything like that.”

“Indeed.” Snape looked for a moment as though he would say something more, but then appeared to catch himself, and change his mind. He turned abruptly away from Harry and began to pace in front of his desk, his rare good humor – if it could be so called – fleeing as quickly as it came. “You did not have to do this,” said Snape, his robes snapping out angrily behind him. “You should not have.”

“You mean the memory?” Harry said, more than a little bewildered at the sudden change. “Why not? It was the right thing to do.”

“I am aware,” said Snape, sounding even more agitated. “That is precisely the problem. You should not have. You should never have done me such a kindness, no matter you thought you should.”

“Why not?” Harry asked again. More boldly, he added, “I know you don't really believe in being kind – um, I mean, sorry, but you aren't, usually – but that doesn't matter. I'm not expecting you to be nice back, you know. I know it was just once, and I wasn't expecting it then, either. Just – I thought it was right.”

Snape paused, then, and raised an eyebrow. “You understand very little,” he said, choking back a laugh. It came out anyways, a singularly bitter and wounded sound, which was all the stranger for having come from Snape. “You know not what you have done.”

“Well... couldn't you tell me? Sir?” Harry asked, and waited for the proverbial axe to fall.

Snape looked him in the eye – Harry tried not to look elsewhere – and then turned, surprisingly, to Dumbledore's portrait. “Headmaster,” he said, “Albus. You seem to have underestimated him after all. And – you will have underestimated me, also.” The portrait attempted to speak, but Snape held up a hand to forestall him. “I apologize for disrupting your plans,” he continued, “but there is, as you well know, a prior claim on my loyalties.” Snape made as if to turn back to Harry, but then halted, and added, over his shoulder, “I apologize for this, too, but I feel it to be necessary. Silencio.” Dumbledore sighed, as if resigning himself to the ban.

“Potter,” Snape paused a moment, and said, shaking his head, “I cannot call you by that name. Harry – if you have no objection?”

Harry knew that if he did not allow it, Snape would not persist – and yet Harry could not find it in him to deny the man, not when there was precious little left to withhold regardless. He knew that it would invite a confidence beyond even camaraderie, but had Snape not, just minutes ago, held him and dried his tears? I am not my father, Harry thought, grasping at once what Snape asked – and offered.

“Of course,” he said, and watched as some of the nearly two-decades-old burden lifted from Snape's shoulders.

“Harry,” said the man, the name strange but not unwelcome from his mouth, “There is much you ought know, and not enough time.” He sat down, in not the headmaster's chair, but one of the two opposite his desk, and motioned for Harry to take the other.

“The Headmaster sought to buy my security in the Dark Lord's ranks with his own life – you can surely see that now. What you did not know – and were not supposed to know – is that he intended to buy, also, a final victory in this war with yours. I was once willing to countenance it – but no longer.” One of Snape's hands clenched spastically around the arm of his chair, going white at the knuckles.

“I know that I'm probably going to die, sir,” said Harry. “I've known that all along. I mean, Voldemort's more powerful, and smarter, and he's got decades of experience on me – I know I'm no match for him. And I know I'm the one who has to face him in the end, since there's the prophecy and all that. It's not Dumbledore's fault.”

“You think you know more than you do,” said Snape, “and you cleave too blindly to the Headmaster's plans. He should have been a Slytherin – and you are no match for a Slytherin in conspiracy. There is undoubtedly a world of difference between the death you envision for yourself and the death the Headmaster has ordained for you.” Snape spat the last few words with a bitterness even Harry seldom saw from him, and shot Dumbledore's portrait a dark look possessed of all the venom of a basilisk.

“What do you mean?” Harry demanded, not quite believing his ears. “What do you mean by 'the death he ordained for me'? Dumbledore didn't want me to die – he made me live with the Dursleys so I wouldn't be killed!”

“That is precisely the point, Pot– Harry. It is not that he wanted you dead in principle, but rather that he deemed it necessary for you to die at a precise moment in the course of the war, in order to break a particular and crucial spell. Had you run afoul of the Dark Lord before then, you would have ruined the Headmaster's carefully orchestrated plans.” Snape said this calmly, as though explaining a simple concept to a first year, but there was a brittleness in his tone that even Harry could perceive.

“It's Dark Arts, isn't it?”

“Indeed,” said Snape, “Horcruxes are the worst sort of Dark Arts.”

“But you need to kill someone to make the Horcrux, not to break it. You only need to break the thing that he put the piece of his soul into and turned – oh. Oh.” Harry clapped a hand over his scar and whispered, horrified, “It's me, isn't it.”

Snape stared at him, the haunted look in his eye akin to the one Harry had seen moments ago in the Pensieve, when Snape had all but offered his own life in exchange for Dumbledore's. “Yes,” he said bleakly, “and I wish to Merlin it were not so.”