"Potter."

Harry jumped and spun in one fluid motion, startled by the sudden use of his name. Snape had approached him, silently of course. Harry had been leaving the Great Hall from lunch with Ron and Hermione. He had noticed that both Snape and Dumbledore were missing when he had glanced up at the head table, and he had a good hunch what was happening. Hermione had commented, but to her, he played ignorant.

"Yes, Professor?" Harry replied, almost hopefully.

"Detention tonight," he drawled. "Seven." Harry looked horrified.

"What did I do?"

"Don't think I haven't read your essay and found the invisible ink with the insults written in the margins," Snape continued. Of course, Harry had done no such thing, and the thought had honestly never occurred to him. The accusation was so far from the truth that Harry began to wonder if that wasn't the point of it. Harry supposed this was Snape's way of getting him alone to discuss the matter of Sirius in more detail, while saving face in front of his friends.

"Fine," Harry grouched, rolling his eyes.

"Fine, sir," Snape corrected.

"No need to call me 'sir,' Professor," Harry sassed. If he was going to get a detention anyway, he might as well earn it. Hermione paled and Ron was failing at hiding a grin of epic proportions. Snape just glared down his hooked nose at Harry, his eyes flashed slightly.

"I can always make that two detentions," he threatened quietly.

"No, sir," Harry muttered, biting the inside of his cheek to keep from laughing.

"Then don't get smart," Snape said very softly. He turned and stalked off.

"Invisible ink?" Ron asked, once Snape was out of earshot. "Are you suicidal, mate?"

"I don't know what he was talking about," Harry dismissed casually. "Maybe one of your brothers wrote something on my essay."

"Nah, they wouldn't do that to you," Ron said.

"Maybe not," Harry agreed. "But hey, if I was going to detention anyway, I might as well have one good line."

"It was funny, regrettably," Hermione pitched in. "But you should keep better track of your essays if you don't want someone to sabotage them."

"Of course, Hermione," Harry said humbly.

At seven, Harry Potter knocked on Snape's office door. He was met with a sharp "Come in!" So Harry opened the door and slipped in. The room was dark and quiet as usual, and Snape sat at his desk pouring over books and papers. Harry sat in the chair opposite his professor's desk and waited for Snape to acknowledge him. Snape cleared his throat and looked up.

"As you may have guessed, this was not intended to be a real detention," Snape began. Harry nodded, but didn't interrupt. "I spoke with the Headmaster this afternoon about your concerns." Snape paused.

"And what did he say?" Harry asked, beginning to worry. If it had been anything good, Snape wouldn't be hesitating.

"He wants me to see the memory," Snape finally sighed.

"Why?" Harry asked, feeling more than a bit nervous.

"He doubts its - authenticity," Snape sneered, leaning back in his chair and resting his chin in his hand as he looked at Harry.

"I thought so," Harry muttered.

"Why did you suspect that he wouldn't believe you?" Snape asked.

"He likes Sirius too much," Harry shrugged. "He wouldn't want to believe that someone from his house - a student of his - has lost it enough to do that. And he hasn't been looking at me since last year."

"Is that it?" Snape asked, meeting Harry's eyes.

"Yes, sir," Harry replied. "Isn't that sufficient?"

"Of course," Snape said, his tone satisfied as he glanced back at the papers on his desk.

"So - I'll have to show you somehow?" Harry asked.

"Yes, there's a pensieve over there," Snape said, gesturing to an oversized bird bath on the other side of the room. Snape rose and Harry followed him over to where the stone basin stood.

"Think of the memory," Snape instructed gently. "I will catch it with my wand and put it in the pensieve. It will look like a silver thread."

"Alright," Harry said, closing his eyes on concentrating hard. Snape must have been able to do what he said he would, because in a minute he brought Harry back to the present with the sound of his voice.

"There," Snape said. "It's in the pensieve." Harry opened his eyes and looked up at Snape apprehensively. "Did you want to stay here while I examine the memory or not?"

"I - I don't know, sir," Harry said, shifting his weight nervously. "Did you have a preference?"

"It's your memory," Snape said. "However you would like it."

"Then," Harry hesitated, "if I could stay here."

"As you wish," Snape nodded, and touched the surface of the pensieve. Snape disappeared inside the bird bath, and Harry nervously sat down in the chair in which he had previously resided.

Harry was glad that Snape had believed him, even if Dumbledore hadn't, which was odd, considering that Snape was always calling him a liar among a myriad of other things. He wondered what Snape had meant by checking the authenticity of the memory though. Maybe Dumbledore was concerned that Voldemort had placed it in his head somehow and it wasn't really true?

But it was true! Harry knew it was true. He remembered it. If he couldn't rely on his memories to be true, then Harry didn't know what he could rely on. He could even tell you the day and time it happened too. He wasn't sure what Dumbledore was hoping to find. That he had made it all up? He hoped Dumbledore thought better of him than that. He would never make something like that up, and he would certainly not incriminate the closest thing he'd ever had to an adult that cared about him.

Heck, he would have incriminated Snape first, he realized, if he were going to make something up. He had no motivation to accuse Sirius of anything that wasn't true. Why couldn't Dumbledore see that? Harry felt hot tears prickling at the back of his eyes.

He must have been thinking longer than he realized because suddenly he was brought back to the present when Snape came tumbling out of the pensieve and fell to his hands and knees.

"Professor!" Harry shouted as he rushed to where Snape was unmoving. Snape looked visibly ill, and as if on cue, Snape heaved and began sicking up. Harry backed away a bit, unsure what to do. When that wave seemed to have passed, Harry took a step closer. Snape drew his wand and cast a quick "Scourgify" to clean up his mess. Shaking a bit, he stood up.

"Are you alright, Professor?" Harry asked.

"I'm fine, Potter," Snape assured him, not too harshly.

"And?" Harry asked, anxiety creeping into his voice.

"And what?" Snape replied, collecting himself further, and banishing the memory from his pensieve.

"What did you find? About it's 'authenticity'?"

"It was a memory, Potter," Snape dodged, as he took his seat opposite Harry behind his desk. "One I would have infinitely preferred not to witness."

"Sorry," Harry muttered.

"Tell me," Snape continued, ignoring the apology, once again looking Harry in the eye. "Why do not want Black punished for this?"

"Because it's not his fault!" Harry insisted, trying to put all the sincerity he felt into his voice. "Sirius does care about me. I don't want to lose that. It's just - I can't be alone with him. It was an accident that he did that. He shouldn't get punished for an accident."

"Be that as it may," Snape dismissed, and his eyes took on a far away look, as though he were thinking deeply about something. After a few moments of silence, Harry slowly rose from his chair.

"Will that be all, sir?" Harry asked.

"Hmm?" Snape grunted as he was pulled from his own private reverie. "No, not quite." Snape pulled open a drawer in his desk and produced a small glass vial with a deep red potion in it. He handed it to Harry. Harry looked from the potion back to Snape, unsure what to do.

"What's this for?" Harry asked.

"The Headmaster mentioned while I was talking with him about the Cruciatus last spring," Snape explained. "This is to help you heal from that."

"I don't know what you mean," Harry said, confused.

"Sometimes there's a few aftereffects," Snape sighed. "Nothing major. This is just to make sure you heal properly. If you already have, then it won't hurt you."

"Oh," Harry said. "Well, I'm fine." He tried setting the vial back on Snape's desk.

"No, drink it," Snape insisted. "I didn't brew it this afternoon just to have it wasted." Harry blinked momentarily, at the thought that Snape had done something with him in mind specifically. "It won't hurt you, as I said."

"Why didn't Dumbledore - "

"It's Professor Dumbledore!" Snape hissed.

"Why didn't Professor Dumbledore give it to me earlier then?" Harry asked.

"Because he's an old fool," Snape explained without missing a beat.

"Because that's more respectful than not calling him Professor," Harry nodded quietly.

"He never told me until today," Snape continued. "I cannot begin to understand the workings of his convoluted mind. I believe it would give me a migraine of epic proportions if I tried."

"You get migraines?" Harry asked.

"Drink the potion," Snape instructed. Harry did as he was told. It didn't taste too bad, and he set the empty vial back down on Snape's desk. "And yes, I do get migraines. Why does it matter?"

"They're rare in males," Harry said. "I get them too, occasionally."

"Interesting," Snape said, though his tone said otherwise. "Dismissed." Harry turned and went to the door.

"Oh, and Potter," Snape called after him. "Good night."

"Good night, Professor," Harry called back.