Over the course of his Hogwarts career, Harry Potter had gotten himself in a lot of trouble. Sometimes, it was well deserved, like when he had flown himself and his best friend into the angry embrace of the Whomping Willow at the beginning of their second year. Sometimes, it was less deserved, such as the countless lines assigned by Umbridge for telling the truth about Voldemort's return. Either way though, Harry was experienced at dealing with detention. And he had been absolutely certain that no school-year punishment could be worse than those lines with the blood quill. He had forgotten, however, exactly how vindictive one Severus Snape could be.

The yank that pulled Harry from the Pensieve had been unexpected, and he almost lost his balance from that alone. He'd barely had time to realize the trouble he was in. The jar of cockroaches sailing towards his head was a good reminder however. With sharply-honed Seeker's reflexes, Harry threw himself to the side. He lost his balance, landing with a grunt on the stone floor of the dungeon. Well, he was usually on a broom, after all.

"How dare you!" Snape roared. The smash of glass against stone made Harry flinch. "You beastly—awful—terrible—" Snape apparently didn't have words.

"I didn't mean-" Harry said, scuttling backwards on hands and feet like a crab. Snape swooped across the distance between then, robes flapping menacingly. The professor's face was dark red and hard with fury.

Harry was in so much trouble. His heart jumped into his throat. Maybe this time, he thought, Snape really would kill him and cut him up for potion's ingredients.

"You are a liar, and a sneak, and a pain-in-my-arse, Potter! Just like your father! Does it make you proud, to see just how alike you are?" Harry couldn't move back any further, as his back was pressed against the dungeon's cold stone walls. Not too far to his right was a mess of shattered glass and cockroach bits. He thought to scramble up, using the wall as a brace, but suddenly Snape was looming over him, trapping him with a foot on either side of his knees. His long, thin hands were shaking with fury as he reached down and got a good grip on the collar of Harry's robes.

Harry flinched backwards, pushing on Snape's sinewy forearm. "Let go of me," he demanded, hoping his voice wouldn't shake. Uncle Vernon had sometimes grabbed him like this. It had never gone well for him after that.

Snape did not release him; Harry hadn't really thought he would. Instead he gave a mighty yank that pulled Harry to his feet. He then shoved him hard against the wall. The force of the impact drove a gasp from Harry's lungs. The stones behind him seemed unnaturally cold.

"Did you enjoy that, Potter? Does it please you to see your most hated professor brought low? To see me powerless?" Snape was out of control, hissing his words mere inches from Harry's face. Small flecks of spit spattered against his skin. He was surprised at Snape's words—Snape did not admit to being anything but powerful. He did not admit to anything, actually. Harry could not remember the professor telling him even the smallest detail about himself before. For the man to admit that he had ever been powerless or taken advantage of, even when Harry had seen it with his own eyes...Snape must be more affected by what Harry had seen than Harry had thought. Or perhaps Snape did not realize what he was admitting to Harry. But he had it wrong!

Harry shook his head frantically. "No! Sir, I didn't—" But again, Snape cut him off with a shake that rattled Harry's bones.

"Well how does it feel to be on the other side of the equation, Potter? To be helpless, unable to affect what will happen to you?" Their noses were almost touching now. Harry turned his head aside, trying to make space between himself and Snape. "It is not so amusing now, is it?" His words were sharp enough to cut.

Harry could see a vein pulsing in the professor's forehead. His eyes were more than half-crazed, and Harry began to feel real fear. The man did not look entirely sane. "Sir, I didn't mean-"

SMACK! Harry gasped when the professor's hand landed hard on his cheek. His head bounced off the stone wall, and an involuntary whimper slipped from his lips. That really hurt!

"For the love of Merlin, Potter, shut up! Have you no self-preservation instincts what-so-ever?"

His cheek was stinging fiercely, as was the back of his head, and Harry blinked repeatedly in an attempt to keep his eyes from watering. His heart was pounding against his sternum. But he stayed silent. When Uncle Vernon got this angry, Harry did his best to get out of his path...and if that wasn't possible, then he kept quiet in hopes that Hurricane Vernon would blow past quickly with minimal damage. Hopefully Hurricane Snape worked the same way.

"Just like your father, Potter. Not enough that I be humiliated-you have to grind salt in the wound. But you forgot something. This is my kingdom, Potter. Down in these dungeons, I am the one with the power. You are the one without. Do you understand that?" Snape shook him hard. There were going to be bruises shaped like the man's hands along his upper arms, Harry was sure.

Harry stayed mute, heat radiating from his battered cheek. Snape's hand came up again. This time, Harry ducked, trying to put his arms in the way.

Instead of back-handing him again, though, Snape grasped his upraised forearm. Harry had never been big for his age, but it had been years since he had felt so small. Snape spun him around and pressed his wrists against the wall above his head. Harry's breath caught in his throat. He struggled against Snape, but the man's weight kept him pressed against the stone. He could feel the pressure crushing the fragile bones of his wrists.

"Did you enjoy humiliating me, Potter?" Snape hissed. "Was that sufficiently entertaining for you?" His grip tightened even more. Harry wondered if his bones would snap under it.

He squeezed his eyes shut, truly afraid now. Snape had lost his damn mind! Harry wasn't even sure if the man knew which Potter he was berating at the moment. And after seeing the memory in the Penseive...that was a truly horrifying thought.

He heard a muttered incantation, and then Snape released his arms. A Sticking charm, he noted in the very small part of his mind that was not panicking. His palms were plastered to the dungeon walls.

"Sir, please!" He hadn't meant to speak, but the words slipped out. He tried to look over his shoulder at Snape, but his range of motion was severely limited by the way his hands had been fettered. With Snape directly behind him, he couldn't see anything.

So it was a sound that stopped his heart—the metallic clink of a belt being undone. His mouth went dry. The small part of his brain that still processed logically seemed to shrivel up and die. "No! Professor, please! Don't!" Harry managed to squeak out. He hadn't thought his heart could pound any harder, but that noise had set it to a whole new tattoo.

Snape chuckled. It might have been the ugliest sound Harry had ever heard, full of malice and spite.

"Potter, I have wanted to do this since the first day you walked into my classroom," he said. The fifteen year old struggled fruitlessly against the magical bonds securing him to the wall. There was a loud whistle of air being displaced from behind him, and then a deafening CRACK!

The pain was searing and immediate, and it brought tears to Harry's eyes. He gasped and clenched his teeth together to keep from crying out.

"For the past five years, I have put up with all manner of idiotic, imbecilic, arrogant stunts from you." CRACK! The belt landed again, like liquid fire against his arse. "And every year, Albus makes excuses for you, his precious Golden Boy." CRACK! "But not this time, Potter. Dumbledore is not here to make excuses for you now. This time," CRACK! CRACK! "you are getting exactly what you deserve."

Harry broke then and let out a low, keening wail. Oh, Merlin this hurt! It had been years now since Uncle Vernon had given him a real thrashing, and he had forgotten the vivid bite of a leather belt.

"I think it's only fair, after all, to deal you a taste of what you dealt me," Snape said, his voice silken and furious. "Do you agree, Mr. Potter?" CRACK!

Harry bit back another sob. The spell held him fast against the wall, despite his struggles to free himself. He wanted to beg for mercy, but he knew better. As a child, his pleas had fallen on deaf ears, and he had no illusions that Snape would treat him any better than his uncle ever had. He gritted his teeth in another attempt to keep the pained noises from Snape's ears.

"Answer me!" Snape demanded. CRACK! Harry jerked, his body pressed flat to the wall in an attempt to flee the agony. CRACK! "Now, Potter!"

Harry knew that he could not win this. If he said no, he didn't deserve this, Snape's fury would increase, and so would the strength of the lashes. If he said yes, Snape would taunt him, and take malicious pleasure in giving Harry what the boy had admitted he deserved.

Harry let out another low sob as the belt bit into his skin again. By this point, his trousers and robe did almost nothing to blunt the pain. His eyes were filling, and he blinked hard, but it was no use. Tears spilled over his cheeks.

"I've waited for years, Potter. I can hold out as long as I must." CRACK! CRACK! CRACK!

The pain was overwhelming. Harry couldn't even think. His mouth was moving before he had a chance to censor himself. "I'm not James!" Harry cried. "Please sir!"

He winced, waiting for the belt to fall again, even harder because of the professor's anger. He had probably just signed his own death certificate. More helpless tears escaped to course down his face.

Instead of another searing crack of the belt, though, there was a profound silence. If it weren't for his own sobbing breaths, Harry might have thought he had gone deaf.

"What did you say?" Snape finally said in a low, menacing whisper. Harry swallowed hard.

"I'm not James, sir. I'm not my father." He tensed and screwed his eyes shut, waiting for the next stripe of pain. Surely now Snape was going to kill him. He'd be lucky to ever sit again.

There was another indeterminable pause. Finally, he heard a clink and a soft thump. "Finite incantatem," the professor whispered, and Harry's hands finally came loose from the stone wall. Harry swiped at his face with a shaking hand to banish the tears he hadn't been able to keep back, then turned on unsteady feet. He couldn't stop the hiss of pain his movement caused. Snape had really let him have it—it had been a long time since he'd last been punished like that. His red, teary eyes went to his least-favorite professor.

The man was standing, his arm down at his side. The belt lay in a puddle on the floor, as though it had slipped forgotten from nerveless fingers. Snape was looking his direction, but his gaze was years away.

Harry was afraid to move. He was pretty sure that the thrashing was over, but he didn't want to catch the professor's eye and remind him that he was still there, in case the man had somehow forgotten. Plus, he was in considerable pain and he didn't think he could just high-tail it out of there. So he stood, looking at his professor who was looking into the past.

Snape's eyes snapped to Harry's own for a mere second before shifting to his cheek. The man grimaced and turned away. "You are injured, Potter," he said, his voice as calm as Harry had ever heard it. The man glided across the floor to the potions cabinet behind his desk. Harry watched, his breath still uneven and a bit shuddery. He had to gather all his Gryffindor courage not to try to run while the professor's back was turned.

Snape appeared to find what he was looking for: a squat brown jar. "Come here, Potter," he ordered.

Harry hesitated a moment, then found his courage and limped over, doing his best to hide the pain the movement caused. He could tell he was unsuccessful however because Snape looked an odd combination of satisfied and nauseated. Snape unscrewed the lid of the jar with his long, pale fingers and scooped up a blob of greenish-gray goop. "Shut your eyes," he commanded tersely. Harry hesitated.

"I will not hit you again. For Merlin's sake, just shut them." A muscle was working in the man's angular jaw.

Wondering if he was being particularly foolish, Harry closed his eyes. When he felt Snape's fingertips press against his cheek, he couldn't help the flinch.

"Cold," he whispered inanely. The professor was silent, his fingertips efficient against Harry's heated skin.

It was a very odd sensation as his most hated professor rubbed the balm into his cheek. He had known it would bruise as soon as the blow had landed, but the sensation faded as the mixture was absorbed into his skin. When the pain had faded to the mildest tingling, like cold air might cause on a brisk day, Snape pulled back. Harry's eyes snapped open again, and for another brief moment, ebony eyes met emerald ones.

"Pupils seem even, but I need to examine your head," Snape informed him briskly. Harry hesitated, then tilted his chin to his chest so the professor could examine the place where his head had impacted the wall. The professor's fingertips palpated his skull, and Harry winced. "You do not appear to have a concussion, Potter. This balm should help with the swelling and pain." Again, Snape used efficient, brisk fingers to rub the balm into his scalp. He could feel the magical healing as the goo absorbed into his skin. The pain of the bump faded into oblivion. "If you become dizzy, nauseated, or sensitive to light or sound, you will need to see Madam Pomfrey immediately. Do you understand?"

"Yes, sir," Harry said quietly. He looked up, his eyes brushing against Snape's own.

Again, the professor looked away. He slapped the jar down on the surface of his desk. "You may take that with you, Potter, to treat your buttocks," he said with no visible sign of embarrassment. "I shall not be assisting you with that."

Harry felt his face flush a brilliant scarlet at Snape's words. "I'll be fine, sir," he managed to stammer, but he reached out with his Seeker's reflexes and snagged the small jar.

"If you wish to play the hero, boy, I shall not attempt to stop you," Snape drawled.

"I'm not! Sir," he added. Then he took a deep breath. "Thank you for this." He wiggled the jar clasped in his hand. "And I'm sorry for invading your privacy, Professor. I was only...well honestly, it doesn't matter the reasons, does it? But I won't do it again, sir. I promise." Harry swallowed hard and looked down at his trainers.

But of course the snarly professor couldn't resist a last jab. "If I had known a good hiding would improve your attitude this much, Potter, I would have turned you over my knee before that damned Hat ever got a chance to Sort you."

Harry felt his face flush. "I'm not apologizing because you thrashed me, sir."

"Oh, indeed? Well, do enlighten me Mr. Potter," Snape said, looking down his considerable nose at Harry. "What caused this sudden change of heart?"

The sarcasm was thick, but Harry was not deterred.

"I don't like bullies, sir," Harry said quietly.

Snape stiffened, and Harry suddenly realized that his words could be taken two ways. Yes, James had bullied Snape and left him defenseless...but Snape had bullied Harry today, and indeed, his bullying was at least as egregious, if not more so, because of the relative differences in power between them. Harry hurried on.

"What I mean, sir, is that my dad shouldn't have done that to you, and I shouldn't have seen it. That's why I'm apologizing. Not 'cause you thrashed me. I might of...err, I mean...well, I shouldn't have looked." Harry shut his mouth then, before he said something that he didn't mean to say.

Snape, from what Harry could see from the corner of his eye, did not know what to make of his apology. Harry looked up then, and his eyes met Snape's own. He got the barest hint of a thought from the man...more a sense, really, that Snape wondered if he was attempting to manipulate him.

Harry locked eyes with the professor and concentrated hard on the feelings of dread, disappointment, and unhappiness that his father's cruel treatment of Snape had caused Harry. Mixed in with it, of course, was the still genuine dislike and distrust of the Potions professor, but Harry figured that would not surprise the man at all. He just wanted him to know how little pleasure he had gotten from the scene he had watched.

He could tell that Snape could feel the emotions Harry had presented for him; the man paled noticeably, then blinked rapidly and turned his head. "Keep your thoughts to yourself, Potter," he snarled. "I have no interest in them."

"Yes sir," Harry replied. He dropped his eyes to his own hands and the small brown jar Snape had given him. His bum was throbbing, and more than anything, he wanted to see if the bruise balm would relieve the pain. A part of him (a rather small part) thought that the whipping Snape had dealt him was at least somewhat deserved, and he had been surprised that the man had offered him the salve. Harry was not one to look a gift horse in mouth, though, and he knew the trek back to Gryffindor tower would be near unbearable without it. And right now, Harry wanted nothing more than to use the salve, put on his pajamas, and crawl into bed to lick his metaphorical wounds.

"Sir? May I go, please?" Harry asked.

"Go," Snape ordered with a jerk of his hand.

Harry made his slow, painful way to the desk where he had left his things. He bent carefully and packed up his stuff, then cautiously slung his bag over his shoulder.

Then something occurred to him. "Um, sir? I have a question," Harry said, turning toward Professor Snape. The man had his back to Harry, his eyes focused on the parchments across his desktop.

"What?" Snape asked. Harry could tell the man was not really paying attention.

"Our next lesson...do you want to...er, that is, are you willing to have another go at teaching me Occlumency?" Harry asked, his eyes on the back of Snape's head. That dark head popped up, and Harry realized he had startled the professor.

"Well, this is new. Tell me, Mr. Potter, what has changed your mind about the subtle art that is Occlumency? I would have thought you would take this dear opportunity to refuse to work with the great, greasy bat of the dungeons." He had slowly turned during his speech until they were face to face. Harry forced himself to meet the professor's black gaze.

"Um...well, I might have, sir, but..." Harry tried desperately to gather his thoughts. "I mean, it's important, isn't it? It could be my only real chance against Vol-"

"Do not say his name!" Snape hissed. Harry flinched at the vehemence in the man's voice, then nodded.

"Yes, sir," Harry said. "But, um, You-Know-Who. I need to be able to keep my thoughts away from his or I'll never be able to beat him. How do you win a duel against someone who knows exactly what you'll do next? So I need to know Occlumency, so it isn't so easy for him."

"And when did you decide this, boy?" Snape asked disdainfully. Harry tensed at the epithet, but then shoved it away. It did not matter. "Did I finally beat some sense into you?"

What an arse. But if Dumbledore wanted Harry to learn this so badly that he would sanction Snape's actions, then it must be important. Dumbledore knew that the two of them got on like porcupine quills and mandrake kidneys-explosively. He surely would not have thrown them together for kicks and giggles. "Perhaps," Harry managed to say, though the word nearly choked him. But Harry knew that these lessons were more important than his pride, or his hatred of the potions master.

"Then I shall keep that in mind," Snape said spitefully. "Since nothing else I have tried has done so."

Harry knew they could exchange barbs all night, but he was sore and weary from the adrenaline leaving his system. All he wanted to do was find the nearest toilet to apply that bruise balm, make the climb back to Gryffindor tower, and crawl into bed. He gave a small nod to acknowledge the professor's words, carefully shifted his book bag across the front of his hip and took a series of slow, painful steps past his professor and towards the door.

From nowhere, Snape's hand shot out and snatched his bicep in a hard grip. Harry froze. Now what?

"If you speak a word-even one!-about the contents of that Pensieve, Potter, you will look back on this night and long for my tender mercies. Do you understand me?" His voice was low, deliberate, and threatening. "I will not be so lenient again!"

"I won't say anything," Harry said. "I wouldn't have anyway." Harry could not explain the shame he had felt seeing his father's casual cruelty. As much as the beating Snape had doled out had hurt, Harry still thought that the pain of watching Snape's memory had been worse. There was no salve to numb it.

"Do you understand me, Potter?" Snape repeated, his voice rising. The madness was creeping back into the professor's voice.

"Yes, sir," Harry replied, hoping Snape would let him go.

Snape's eyes locked on his. "Legillimens," he said. Harry struggled mentally as the man ripped through his mind, examining all the thoughts and feelings attached to the last twenty minutes. Harry was helplessly lost in the riptide of his own mind. Stop! Please, stop! he wailed inside his head. Reliving the fear and pain of the whipping, not to mention how much it reminded him of his family's less than tender treatment, was almost more than Harry could bear. STOP! Harry begged mentally as tears sprang again to his eyes.

And then Snape released his mind. Harry sagged, and if the man hadn't been clutching his bicep in a death grip, Harry might have collapsed onto the floor.

"I see that you do," Snape said coldly. Harry nodded weakly, and Snape released him with a mild shove. Harry kept his balance mostly by force of will.

"Leave," Snape said.

And Harry hobbled off as fast as he could, desperate to leave an angry Snape and the dungeon behind.

So Harry did not see the man slump, leaning hard into his palms on the surface of his desk. He did not see the lank black hair swing forward and obscure the shame and grief on the professor's sallow face. And he did not hear the whispered words, rough with pain, escape from that usually silken throat.

"I'm sorry. Oh Lily, forgive me for hurting your boy. I'm so sorry."

And a lone tear slipped down the man's cheek.