If Snape made one critical error, it was underestimating Harry's capacity for deception. After several minutes of quietly celebrating his success at dissuading the boy, his reason overrode his pride, and it was suddenly glaringly obvious what Harry was planning to do.

By the time he stumbled out of his half-mad charge to the hospital wing, his son was already hovering over Granger's bed, wand drawn. The dark head shot up in alarm upon Snape's arrival, and Severus detected the faint blue flash of a shielding charm flickering to life around Granger's bed.

"You have not yet performed the spell," Snape said, half in question.

"Just back off," Harry said, meeting Snape with a cold, level gaze that told him the boy knew exactly how he'd tried to mislead him. "You can't stop this."

"Think about what you're doing!" Snape bellowed. "For once, don't be a rash fool!"

"There's nothing rash about this," Harry retorted. "If this is going to save Hermione, I don't give a damn who told me about it. I'm using it!"

"For Merlin's sake, boy-- the Malfoys want us both dead!" Snape roared. "That Wizard's Debt gives you leverage. If you throw that away, you will have nothing! "

"I don't CARE! She's my friend, and she's dying!"

Snape drew closer to the invisible barrier, mind racing over counter-shield charms; Harry's wandwork was too quick for a direct assault. He needed to take him by surprise… he needed to stall.

"Lucius knows about us."

Harry froze. "What?"

Snape watched him closely. "He murdered several of my relatives, searching for Septimus." At Harry's stunned look, he felt compelled to add, "He was seeking to revenge himself upon me for his humiliation at my hands. He learned in the course of interrogating my-- our relations that Septimus Snape does not exist."

He held Harry's eyes with his dark ones, silently willing the boy to relax his guard.

"Lucius has since deduced that the boy he met this winter is my offspring, product of an illicit liaison. How long before he looks further into the matter and uncovers your true identity? You will not be long for this world once he knows the truth. Draco's debt may very well save your life. But only if you preserve it. Do not use that spell!"

Harry shook his head, undaunted. "If it wasn't her…" His eyes trailed down to Granger's sleeping face, pale and wasted in the dim light of the hospital wing. "I can't lose Hermione… she's my best friend--"

"She's your best friend," Snape echoed in a nasty, mocking tone, his patience frayed. "What does that matter? You're so terribly eager to play the martyr, I believe you'd throw your life away if it was the Dark Lord himself lying on that bed!"

Harry's gaze snapped back up. He stared at Snape, confused, seeming to fumble for a retort that never came.

A slow, horrible grin twisted Snape's sallow face. Like some predator that had just scented blood, he stalked closer to his son.

"Tell me, Harry-- what was it you hoped to accomplish that day in the woods?" he said in a soft voice that mocked tenderness. "Was it really Bellatrix you intended to destroy? Or was your vendetta against her merely another instance of rank ­self-delusion?"

Harry's eyed him warily. "What are you talking about..?"

"I am not blind," Snape spat. "When I saw you that day, planning to kill Lestrange, you were completely willing-- pleased, even, to execute it, despite knowing it would rebound upon you!"

Snape stalked closer, dropping his voice to a lethal whisper.

"Or perhaps you were pleased because you knew what that spell would do to you? Could Lestrange's death have merely been a side benefit?"

Harry looked befuddled. "I wanted her to pay. That was all."

"So you claim," Snape sneered, his black eyes glittering. "But I don't believe for one instant that it was pure revenge. Your every action betrays you-- your inability to occlude without that cupboard that lets you imagine yourself in another place, your retreat into self-isolation upon Black's death… It's not a thirst for vengeance that drives you, it's your desire to flee! And what was your attempt upon Lestrange but an escape attempt? You knew full well that kinship curse would kill you. You were counting on it-- the final flight of Harry Potter from his daunting responsibilities!"

An odd look stole across Harry's face. "That's not true. It's not! I'd never do that--"

"It was an escape attempt," Snape insisted, "and one perfectly compatible with your misplaced sense of guilt over the misfortunes of those around you." He drew back a step and surveyed Harry like some strange insect, all the while waiting-- waiting-- for the boy to lower his wand. "You refused to poison Lestrange. And I did not understand why until I listened to what that bloody werewolf had to say about you."

"You've been talking to Remus about me?" Harry said, sounding uneasy with the idea.

Snape smiled coldly and did not acknowledge the question.

"Revenge," he said, "was never your sole motivation… There was a more pressing concern underlying your every action. When you told me about the prophecy, you informed me that every occlusion attempt finds you dwelling upon your responsibility-- and perceived inability-- to destroy a far superior opponent. You clearly do not believe you will succeed--" Snape caught himself just in time to stop the "nor should you" from escaping his lips, and instead continued, "And you are tormented by the prospect of failure. Lestrange gave you an excuse to escape this torment. She gave you a pretense."

Harry stared at him, appalled. "I would never-- I wouldn't do… that."

"Oh, you would never admit it," Snape said derisively. "Not even to yourself. That infernal Gryffindor pride would never permit such a cowardly action… But vengeance against Lestrange was simply a permissible disguise. I robbed you of your pretense in the woods when I told you we'd destroy her together. I did not rob you of the desire."

Harry's cheeks flushed into two spots of angry red. "I think you're just saying this because I didn't want to poison her," he said coldly. "I told you it wasn't enough. She deserves something worse. It's not enough."

"No, it's not enough" Snape replied coolly. "You hate her, I'm certain you wish her ill, but I have come to the unfortunate conclusion that you are not nearly as vindictive as I, and her death alone will never satisfy your needs. It offers you no escape. And you cannot deny this to me, Harry-- you know you do not want to face that prophecy."

He watched Harry's face closely, and he could see that the boy was considering his words, however much he disliked them.

"And now," Snape said darkly, "you seek to escape yet again… Lucius will destroy you if you use that spell, you know it, yet still you pursue it. Here is yet another opportunity for a frightened little boy to escape his problems, another excuse not to fail!"

Harry's troubled expression cleared, and his green eyes riveted sharply to Snape's.

"No, you're wrong there, Professor," he said with quiet conviction. "I get what you're saying… And although I don't agree, maybe it's something to think about… But you're wrong now. This isn't about me. It's about her."

Snape realized instantly that he'd overshot the mark. The uncertainty was dissolving from Harry's expression, and a fleeting look into the boy's surface thoughts warned him that he was growing calm and determined.

"I'm going to save her," Harry announced quietly. "And I'm sorry if you have objections, but you won't be able to knock down my shielding charm and take my wand in time before I use it."

Snape fumed silently, knowing it was true.

"I'm not a coward," Harry said, almost to himself. "She's my friend, and I love her… I'm sorry that it bothers you, but I'd never let someone I love die just to save my own skin."

It took a moment for Severus to catch the implication of the words. He felt the blood drain from his cheeks.

"Unlike me?"

He could kill the boy. He could murder him.

Harry sent him a questioning glance, but Snape was blind to all but the dark rage frothing in his veins.

"You dare to use that?" Snape whispered viciously. "You presume to assert that your petty little dilemma is even remotely similar? You stupid, naïve little fool-- YOU KNOW NOTHING ABOUT ME! NOTHING!"

"What are you talking about?" Harry said, alarmed at Snape's inexplicable reaction. He seemed… confused.

Severus stared at him for a long moment, at a loss. And slowly, humiliating comprehension dawned-- there had been nothing pointed about his son's words… no sly allusion, no attempt to strike out.

He had not even been thinking about what Snape did to his father.

Feeling a lingering anger towards the boy tinged with not a little bit of humiliation, Snape turned inward, groping for a deadlier weapon… Deadlier, colder. Something that would hurt. Something that would work.

All that was dark and cold within him recognized it instantly, the sharpest blade, the one with the deepest cut and the poisoned tip… One he was bastard enough to use.

"Very well, I know you cannot bear to see her in this condition," Snape said, lowering his wand. "Heal Granger if you wish."

Harry's eyes lingered on him warily; they both knew this was not the final word, and his son already seemed to be bracing himself for the inevitable strike.

Smart boy.

"I give you fair warning, though, Harry," added Snape quietly, catching Harry's green eyes with his own. "If you save your friend, you destroy someone else."

He let the words hang on the air for a long moment, watching Harry's eyes widen imperceptibly. Snape wasn't sure if the strange sensation that fluttered in his gut was anticipation or-- Merlin forbid-- a twinge of conscience.

"You destroy me."

Harry stared at him for a long moment, too surprised to react. Then, "This has nothing to do with you."

"Oh, I beg to differ," Snape countered softly. "Our fates are linked now, they've been joined since the moment Malfoy laid eyes upon you in my home. If you play into Draco's hands and absolve him of his debt, we will have no defense against Lucius. Use this spell on Miss Granger now, and you do not merely throw away your only leverage, you throw away mine. You will destroy me… You will…" the words lingered on his tongue a moment, almost too brutal for even him to deliver. He said them nonetheless.

"You will kill your father."

Harry stared at him, as if he couldn't believe Snape would strike so low.

"That's not fair," he said. "Don't say that."

Snape remained unmoved, noting with his calculating, black eyes the boy's eroding confidence. "I am only stating the truth, Harry. If you use that spell, you are making a conscious decision that will lead to my death. Is that truly what you want? Do you wish to be an orphan again? I only wish to inform you of what you'll be doing if you take this action. You will be killing me. You condemn me to die."

Harry looked horrified. It was enough to make Snape feel slightly ashamed, but only slightly.

"Do it, then," he challenged quietly, gesturing towards Granger with an elegant wave of his hand, never taking his eyes from Harry. "Kill me. Use Draco's spell, and be done with it. Become the next Snape to murder his own father. Save your friend, and throw away your family. You've never much cared for me, after all, and I've been less than kind to you. It may even give you some satisfaction to see me dead. I certainly never mourned my own father after I killed him."

Harry looked like he'd been struck. "I-- how can--" He sputtered for breath a moment, then argued passionately, "You didn't kill your father! Voldemort killed him. You told me that!"

"I told you that a Death Eater killed him," Snape replied coldly. "A Death Eater."

The implication hung on the air. Harry's eyes widened with horrified comprehension. "But… how?"

Snape felt his lips twist into a sneering smile. "I told you that it was my reward for my faithful servitude. I was summoned to my master, and before him waited my father-- on his knees. He'd been tortured for hours. It was a scene of my own conception. The Dark Lord knew how many times I'd fantasized about it-- about my father begging me for mercy, begging me not to hurt him, pleading with me not to kill him… The Dark Lord was fond of me, and he wished to see one of my greatest desires come true. And my father certainly pleaded. I fired a Killing Curse, and then he was dead."

Harry stared at him as though he wanted to look away but couldn't bring himself to do so. Snape's eyes drifted to rest dispassionately on Granger, and he found himself speaking again, wanting to hammer brutal word after word into the air between them:

"His death was born of my desires and ultimately done by my hand-- but I maintain that I am not responsible for killing him." He glanced at Harry briefly and, as expected, found that the boy looked repulsed by him. He glanced away again. "I was a loyal servant of the Dark Lord-- as faithful a Death Eater as any-- and what I chose to do that day was not murder to my father, but to accept my Master's gift. I chose to preserve his faith in me by accepting his generosity."

He glanced up briefly; Harry was still staring at him with morbid fascination as though watching a terrible accident. Severus wanted to legilimize him, but he couldn’t hold the boy's eyes long enough. He found himself staring again at Granger's inert form-- one of her pale hands where it rested unmoving against the white bedsheets. She seemed at the moment the most innocuous object in the room.

"Had I killed him of my own initiative-- and eventually I would have-- I could have claimed that I murdered my own father. From your perspective, I'm certain you see it that way regardless." He finally forced himself to meet Harry's eyes. "But guilt and responsibility are all in one's mind. I have chosen to perceive the Dark Lord as responsible for the death of my father, just as you doubtlessly perceive me as the guilty party."

Harry was still staring at him, horrified. Snape felt a stab of dark anticipation as he added: "Just as I know you will ultimately assume upon yourself responsibility for my death, once you cast this spell."

Harry broke the gaze this time, swallowing hard.

"So I ask you, my son," Snape said quietly, "Will you squander Draco's Wizard's Debt and condemn me to death, or will you leave Miss Granger in her current state? Our fates are in your hands."

Harry raised his eyes again, anger blossoming in their green depths.

"You bastard."

Snape raised an eyebrow, considering and then rejecting the notion of pointing out which of them had been born in wedlock.

"You absolute bastard," Harry whispered harshly, his voice rising with anger. "You know what you're doing, you know it! I hate you. I hate you for this!"

Severus let the silence speak for him as Harry cast his furious gaze between his father and his friend, his jaw tight as though he was grinding his teeth with sheer frustration. His fist clenched and unclenched around his wand.

The debate was clearly raging in the boy's head; he neglected to realize that Snape had already made the choice for him. He didn't realize his wand had dropped sufficiently, his distraction was great enough, that now was the time to act. And right as the boy looked at Granger again, Snape spell lashed out and collapsed Harry's hasty shield. Before the boy could so much as fire off a return hex, his wand was flying into Snape's hand.

Snape pocketed Harry's wand, feeling his son's burning glare on him like a tangible heat. He locked his eyes upon Harry's, his triumph fading somewhat at Harry's distraught expression.

"You were distracting me," Harry said. "Weren't you? That was all a distraction."

Snape chose to ignore the question. "Back to Gryffindor with you, Mr. Potter." He waved Harry towards the door with his own wand. "It's well beyond curfew."

Harry lingered, dragging his gaze back to Granger, clearly torn about leaving her. Content in his possession of both wands, Snape did not force him. He felt a small niggling of unease at what he'd just done. Perhaps he should simply have fought the boy first…

Well, he'd let Harry stay with Granger a few minutes more. This was the last time he'd see her for long time. He would smuggle Granger out-- merely until Draco's debt was used properly, and Lucius was taken care of. Surely she wouldn't die anytime soon, would she? He could research an alternative treatment. Refoveo merely gave him grounds to start.

Or perhaps he'd just act quickly. He'd use the debt, secure Draco back into custody, and then he would put an end to Lucius, once and for all.

No Killing Curses. No Absynia. Something sudden. Something painful. Something fitting for a Malfoy.

Harry spoke abruptly, "Did you ever feel guilty?"

Snape drew himself rigid.

"Guilty?"

Harry cast him a sideways glance as though he were only daring to look at him. "About your father."

The question caught Snape off guard. His fingers tightened instinctively around his wand, but Harry had resumed gazing mournfully at Granger's unconscious form, so he relaxed just a fraction.

"I hated my father."

"I know you hated him," Harry said distantly. "That must have made it so much worse, huh? You hated him, you wanted him dead, and then he died… all because of you."

"Forgive me if I do not follow your logic."

Harry glanced at him again in that odd way, and Severus suddenly came to the uneasy realization the boy was paying careful attention to his expression… just as he always did to the boy.

"You said Voldemort acted on a fantasy straight from your mind," Harry explained in an almost gentle tone. "But it was a fantasy… You never actually planned it. Every time your father was a bastard to you, you could look forward to the day you made him pay for it, you could imagine hurting him. But if you'd really wanted him dead, you could have killed him yourself. Even without magic! You could poison him, stab him, strangle him--"

Snape cut him off abruptly, "You betray a lack of refinement, Mr. Potter. I assure you, I wanted him dead… just not in so simple a manner. I was biding my time."

"I don't think so," Harry said with infuriating calmness, still watching him closely. "You see, when I really hated you, I'd imagine using the Cruciatus curse on you and watching you scream, or I'd imagine dumping a cauldron of poison over your head…"

Snape fell silent, thrown off by the turn in the discussion as much as by Harry's words.

"Or after Sirius died," Harry continued conversationally, "sometimes I'd imagine that soon Voldemort would catch you and kill you. I'd imagine letting him see you were a traitor in my mind so he'd kill you. I had fantasies about hurting you because I couldn't do anything else... You were always so awful to me, and the only way I could make you sorry was in my head."

Snape truly didn't care for this line of discussion. It was increasingly disturbing.

"What. Is. Your. Point, Potter?"

"I can't imagine how I would have reacted if it had actually happened, though," Harry admitted, watching Snape with what he suddenly realized-- damn the bloody boy to hell!-- was pity. "However much I hated you, I think I would have felt so awful if you'd actually been tortured, if you'd actually been killed. I'd always feel guilty, knowing I'd wanted that for you once. I would probably always doubt myself for wishing such horrible things for you, and then having them happen… maybe I'd always wonder if I'd contributed to it somehow--"

"If you are trying to draw parallels between the two of us," Snape snarled, "I'd like to point out that crippling sentimentality is your failing, not mine!"

"And you weren't even my father back then," Harry continued, steadfastly ignoring him. "But he was your father. Your family. And it wasn't just a coincidence that you wanted it and it happened… he was killed because that fantasy was in your mind." He held Snape's eyes unflinchingly. "He was your father, and he died because of you… You even had to kill him-- you didn't have a choice! Voldemort made you kill your own father. And you had to live with the fact that he did it because you'd wanted it. That must have been horrifying. I can't imagine how awful that was for you."

Everything in Snape wanted to lash out of the boy for his presumption, but it felt as though his throat was suddenly blocked off and he couldn't manage a word.

"I knew Dumbledore would never believe in a monster," Harry said, with that damnable understanding in his eyes. "But I bet it's always been easier to tell yourself you wanted him dead than to admit you didn't… This way you don't feel guilty, you don't regret. Or at least, you don't think you do. And you don't have to live with your father dying because you were stupid enough to believe in Voldemort. You just tell yourself it's what you wanted all along, that there's no reason to feel bad about it. It probably hurts less that way."

Snape remained frozen in place. Wild thoughts of hexing the boy passed through his mind, but his arms remained locked at his sides as if he'd been paralyzed.

"I know how it feels," Harry said quietly. "You don't even have to say anything… you don't have to admit it. You can yell at me if you want. I just want you to know that I know how terrible it is to be at fault for something like that. I do understand."

A strange feeling like he was choking clogged Snape's throat. He wanted to strangle the boy. He wanted to strangle him.

But he couldn't even move.

Harry finally looked away from him, releasing him from that stranglehold of compassion.

"I don't want to lose Hermione," Harry said quietly. "But I don’t want to lose you, either. Not just because I'd feel awful about it… but you are my father. And you've-- I think you've been looking out for me like one, too."

He peered up at Snape with a strange trust in his expression, and Severus felt an increasingly familiar, sick feeling in his stomach.

"What should I do?" Harry questioned gently. "What do you really think I should do?"

Snape felt a weight pressing on his chest; suddenly it seemed there was far more at stake than merely their lives.

"Please," Harry said, "Tell me what I won't hate myself for. Tell me what I should do."

Tell me how not to end up like you!

The phantom words stung him like bile. Although a tiny corner of Snape's mind still screamed in fury at this gentle manipulation, he'd never before felt so helpless against it. He felt like he'd been torn open by the boy's ridiculous assertions.

They were absurd. They were unfounded. And they'd left him undone.

And now that Harry was doing something so horrendous as trusting him to make the right choice, the decision-- so icy clear before-- seemed muddled and clouded. It had been so easy to face an adversary… but this… This was so much greater… It was so much worse.

He stood frozen before Harry, paralyzed. He could not help but remember that distant night when he'd made another decision that had seemed in many ways so obvious, in others so murky-- the decision to take the life of a man he'd long hated at the behest of his Master-- and he felt suddenly as though he could never make a decision again.

Harry watched him attentively.

At length, his son seemed to comprehend his paralysis. Harry drew closer and gingerly worked his wand out from within Snape's robes, moving slowly and carefully. All Snape had to do was reach out and stop him.

Severus made no move to do so, feeling sick and almost faint.

Grasping his wand, Harry held his eyes for a lingering moment in question. When Snape gave him no indication, he turned towards Granger and raised it.

A soft-spoken "Refoveo" whispered through the air as though from a distant dream. Granger drew a sharp breath that filled the hushed room as she abruptly snapped back into the waking world.

Snape's eyes closed against his volition, almost unable to bear this.

It was only when he instinctively felt Harry come back to his side that he heard the faint whisper:

"Don't worry about Malfoy. We'll stop him. I swear that to you… father."

Harry's quiet promise lingered in Snape's mind long after he dared to look, dared to see his son hovering over his friend-- smiling, whispering quiet assurances to the still disoriented Hermione Granger.

He found himself turning mechanically on his heels, and starting the long walk back to his chambers.

As he emerged into flickering torchlight of the Hogwarts corridors, it seemed that he was emerging into an alien world. They had just thrown away their sole advantage, and his mind told him that Harry's ridiculous assertion was unfounded, ignorant, and completely foolhardy. He couldn't say in that instant why it struck him so powerfully as prophetic.

But something felt very different, lingering on the air about him.

It was the same sensation from when he'd first known Dumbledore, that terrible optimism of faith. He was afraid that this time, it might not fade away. He didn't know if it could.

He didn't know if he wanted it to.