Author's Note: An extra update today, for those who have been waiting for more Snape.

Hermione groaned, and ran her fingers through her hair. It had long since escaped from its knot, and flared around her head in its usual bushy mess. She knew she must look like a fairly good impersonation of Medusa, but she was too tired to care.

It was already half-way through October, and they were no closer to learning who had cursed Professor Snape. Hermione had interviewed everyone on staff who'd fought in the Battle of Hogwarts and owled all the other survivors, and after three weeks she'd been forced to conclude that the death of every Death Eater declared deceased had been witnessed. Harry reported that Kingsley Shacklebolt's investigation had turned up absolutely not a whisper of an undiscovered Death Eater. Luna had spent hours pouring over back issues of The Prophet and The Quibbler and reported odd, sometimes interesting, but always irrelevant details. Ron had resurrected his friendship with Jimmy Simpson but Hermione suspected they spent most of their time talking about Quidditch. He certainly hasn't learnt anything that seems useful. Neville had collected a list of students most often found where they shouldn't be over the past five years, but cross-checking them with Death Eater families, or the families of Death Eater victims, had turned up only a few tenuous links. And Ginny …

Hermione sighed. Ginny Weasley had formed a strong opinion that there was some hidden meaning in Aberforth Dumbledore's drunken ramblings, and had set herself to collecting recollections about Severus Snape from everyone who'd know him as a colleague. Her stories were interesting, and occasionally amusing, but Hermione couldn't see how they were useful.

So what if he argued about Muggle methods with Charity Burbage? She's not likely to have come back from the dead to curse him because he refused to contemplate centrifuges.

Snape had said he had perhaps a year left to live, and a month of that year was already gone, and they were no closer to saving him …

Hermione had done her best to improve the most powerful healing potions she could brew using similar innovations to the anonymous potioneer people called 'The Man of Mystery' in the hope they could buy more time. She'd left them in the Potions storeroom with a note, and they'd vanished, so she presumed Snape had taken them, but whether they'd had any effect or not, she had no idea.

Hermione scrubbed her hand over her face. And I still have all this blasted marking!

Good effort but you have failed to take into account the interaction between ingredients (see page 34) she wrote across the bottom of the essay in front of her, and graded it Acceptable. Placing it on the pitifully small pile of finished papers, she picked up the next.

"Troll," Professor Snape's silky voice said directly behind her and Hermione nearly jumped out of her skin. She twisted in her chair and saw … nothing.

Alright, I admit it, I'm being driven completely around the twist by marking. Probably not the first or the last teacher to completely lose their marbles after reading the exact same turgid regurgitation of the textbook, for that matter.

She turned her attention back to the essay. The Confounding Conconcotion is made from …

"Troll," Snape said again, and as Hermione gasped in shock, his long arm reached over her shoulder, one slender finger landing precisely on the spelling error. "There's no need to read further, Granger, if the student can't even get the name of the potion correct and misspells their error."

"Professor Snape," Hermione said, and had to pause to try and let her heart-rate return to normal.

He strolled around the desk and stood in front of her, folding up what looked suspiciously like Harry's Invisibility Cloak. He had left off his billowing teaching robes, and without them, his lean form in his long, fitted coat looked angular and severe. "Professor Granger."

"How long have you been standing there?"

"Long enough to see that you are expending needless effort," he sneered.

"You can't do that! Creep up on me all invisible and watch me without me knowing?"

One eyebrow went up, nearly to Threat Level Five. "And did you take Potter to task with the same vehemence when he made a habit of doing precisely that as a student?"

"He didn't creep up on people and stand around reading over their shoulder!" she shot back. "How long?"

"Did you completely fail to notice the door opening and closing?"

"I —" That had been a good fifteen minutes ago. "I thought it was a draught."

"Yes, because these dungeons have always been so very prone to extremely high winds." With a flick of his wand, Snape drew one of the over-stuffed chairs to him. He studied it with disdain, flicked his wand again, and watched with a faint air of satisfaction as transformed into the sleek black chair that had graced this office during his tenure. He seated himself in a swirl of black robes and studied her. "I do wonder sometimes how you managed to survive months on the run from the Dark Lord when you clearly lack even basic caution."

"I tend to be less alert when I'm in my own office," Hermione said tightly.

"Foolish."

She kept a grip on her temper with effort. "Can I help you with something? Or were you just spying on me for the fun of it?"

He regarded her over the top of his inter-laced fingers. "I was returning from a walk when I saw the light beneath the door."

"A walk?" Hermione repeated.

"Yes, Professor Granger, a walk. Your acute intelligence is adequate to understand the concept? One foot in front of the other, progress in a forward direction?"

She scowled at him. "I know what a walk is, I just wondered why you'd be wandering the grounds at this hour!"

"Even with Potter's cloak, traversing the corridors when they're crowded is … unwise," Snape said. "And seeing your light, I admit to a certain curiosity about what held your attention at, as you say,this hour. Perhaps a new issue of Potions Quarterly? A groundbreaking new academic paper? Your own promising research, perhaps?" The corners of his mouth turned down. "Imagine my disappointment to learn that you labour into the small hours merely due to inefficiency."

Hermione gave a delicate snort. "Yes, I'm sure it was crushing," she retorted, and was almost certain she saw a glint of humour in his dark eyes.

He gestured at the tiny pile of marked essays, a mere flick of his fingers. "There is no need to waste your time on students too inept to achieve even an 'A'."

Deliberately, Hermione poised her quill above the essay in front of her. "If I don't spend time on them, they'll never improve, will they?"

"Granger, just tell them to do it over. Eventually they'll work out how to get it right — or ask someone who already knows." He shrugged slightly. "Or accept that they lack all aptitude for the subject, and cease to clutter your classroom."

"That might be what you did," Hermione said, "but I happen to think that —"

Snape raised an eyebrow. "Working yourself to collapse is an excellent teaching strategy?"

"I am not —"

"Granger." Snape leaned forward, gaze holding hers. "It is four o'clock in the morning, and this is the third time this week I've seen the light under your door at this hour. If you labour under the illusion that you are immune to the effects of fatigue, I suggest you avail yourself of a mirror."

Hermione's hands rose automatically to her hair. "I hardly expected to receive a visitor," she snapped, trying to twist the curls into a knot at the base of her neck.

Snape sighed. "I wasn't referring to your grooming, although Merlin knows it could be improved."

Stung, Hermione lowered her hands. Being lectured by Severus Snape on personal grooming, that's got to be a new low. "If you've just come here to insult me, you can bloody well leave."

"I came here to advise you not to waste your time on tasks beneath you." Snape began to unfasten the buttons at his left wrist. "You have a reasonable grasp of classroom practises —"

"You've been watching me."

"Of course. Do thank Potter for me." The buttons undone, he rolled the sleeve up to the elbow with precise movements. "And you have a strong, if derivative, grasp of the principles underlying potion innovation." He pushed up his shirt-sleeve and turned his arm to face her. "As you see."

The sickening grey of the curse was still there, but —

Hermione rose to her feet, Snape's insults forgotten. "It's better."

He gave a small nod. "In the comparative use of the word, if not the absolute. Your potions appear to be effective."

Hurrying around the desk, she took his wrist before he had the chance to protest and turned his arm so she could get a better look. "Not really mine," she said absently. Yes, it's definitely smaller. "I applied the principles from an improvement to basic healing salve that were published last year — how quickly did you see the effect? How many doses have you taken? Would increasing —"

Snape reclaimed his arm with a twist of his wrist and pushed his sleeve back down. "Gryffindor honesty. I wondered if you would admit the truth, or claim credit for my work."

Hermione gaped at him. "Your work — you're the Man of Mystery!"

He scowled up at her as he re-buttoned the sleeve of his coat. "I am not. I am an anonymous correspondent. What the inane and inappropriately named The Prophet might write is beyond my control."

"No, I mean —" Hermione took a breath. "I had the chance to analyse your improvements. And you're right, they're the basis for what I did with the potions. But more than that — they were effective." She realised she was rubbing her arm, and stopped.

Snape's gaze flicked from her arm to her face, and back, and then back again. He finished fastening his sleeve, and extended his hand. "Show me."

Hermione took a step back, folding her arms. "It's just an old scar."

He waited, hand outstretched. "That still bothers you. Show me." When she didn't move, he raised an eyebrow. "Come now, Professor Granger. I showed you mine."

Hermione stared at him. Was that … a joke? Did Professor Snape just make a joke?

As inconceivable as it was, it seemed to be true.

And really, compared to the decaying flesh caused by a killing curse, how bad can an old scar be?

She pushed up her sleeve, turned her arm and showed him the faint silvery mudblood engraved forever on her skin.

Snape raised his hand and for an instant Hermione thought he was going to touch the scar. She braced herself, but he stopped an inch before his fingers reached her skin. He ran his hand down her arm, keeping the same distance, and back again. "My salve should have erased that," he said at last, voice and face expressionless, and turned away.

"It's ever so much better," Hermione said, pulling her sleeve down again. "With the new salve. Your new salve."

"I'm glad to hear it." His back was to her and she couldn't see his face, but his voice was still utterly even. "However. It still pains you."

"Only a little."

Snape swung back to face her at that, and his eyes glittered in a face as white as chalk. "Only. A. Little." His mouth worked, as if he were about to spit. "Marvellous. Who gave you that?"

Malfoy Manor and her face ground into a carpet that smelled of dust and blood and the pain, the pain — Crucio! and again and again and then a new agony, sharp, focused — "Bellatrix Lestrange," Hermione managed to say, her voice sounding high and far away to her own ears.

Snape looked away for a moment, and when he turned back his face was once more set in his habitual expression of boredom and contempt. "Of course. Bella always had a problem understanding the idea of leaving alone what she had no right to touch." He looked Hermione up and down. "Continue using the salve. I will brew a potion that will also help. And kindly do not make my task more difficult by continuing to neglect your health." He put one long-fingered hand on her shoulder and turned her towards the door. "Sleep more than a few hours a night. Eat more than sandwiches at your desk. Go outside occasionally. Are these instructions simple enough for you to comprehend?" He gave her a push towards to the door.

"My marking," she protested, resisting.

"I think I can be trusted with that pile of drivel your students so loosely call 'essays'."

"And when they wonder about the handwriting?"

The corner of his mouth turned up. "Tell them you have a teaching assistant. One with decidedly higher standards than yours. Go."

He pushed her towards the door again, and this time, Hermione went.

The next morning, as she applied herself to a breakfast that almost rivalled Ron's, Hermione had to admit that Professor Snape had been right. Instead of setting her alarm for five, in order to squeeze in another few hours of marking or lesson preparation, she'd slept until there was barely enough time to wash and dress and make the Great Hall for breakfast.

And she felt significantly better.

When she reached her office, she was almost expecting to see Snape there. The room was empty, even after she cast a quick Homenum Revelio. The essays, though, were there, neatly stacked. Hermione glanced at the one on the top of the pile, and winced. Everything after the first paragraph was struck through with one slashing red line, and Professor Snape's spiky handwriting — so familiar from her own student essays — down the margin. Not only incorrect, but intolerably dull — D.

Scanning the essay, Hermione was forced to agree with Snape's comment. Although I wouldn't have phrased it that way myself.

There wasn't time to remark all the essays. Resolving not to let Snape loose on them again, no matter how tired she was, Hermione gathered them up and headed to her first class.

The first two classes were uneventful, if tiring — Hermione had yet to work out how to keep a class silent and attentive without effort, the way Professors McGonagall and Snape had always managed. She was just congratulating herself on a successful morning's teaching as she supervised her first year students crushing Moondew when there was a clatter from one of the Ravenclaw tables.

Hermione whipped around to see Michael Rowland looking sadly at his pestle — which was in three pieces.

"How did you manage to do that — no, don't sweep it —"

Too late. Rowland brushed the partially crushed Moondew to the side, straight into the already-prepared pile of Billywig stings. They flared up in a painfully bright reaction, which jumped from Rowland's table to Wilkins and Aitkins before Hermione could cast a containment charm.

"Oh no," Rowland said, horrified.

Hermione forced herself to count to ten, slowly. "Mr Rowland, one foot on why we never mix different ingredients except exactly as called for in the recipe, by Friday. Ms Wilkins, Mr Aitkins, you'd better get fresh supplies."

"I'll get them," Aitkins said quickly. "Maisie, you clean up the bench."

Hermione kept an eye on Rowland as he miserably wiped up what was left of his ingredients, but he didn't seem to be prone to any further mistakes. In fact, I'd hardly think he was the most likely student to have made that error in the first place.

I should probably ask him after class if there's something worrying him —

And she heard the soft but unmistakable sound of Professor Snape clearing his throat.

Hermione spun around, but of course he was nowhere to be seen. Out of the corner of her eye, though …

"Mr Aitkins." Three strides took her across the room. "Why do you have a pocket full of rat tails?"

Colin blinked up at her. "I, er —"

"Turn out your pockets, please." Hermione was quite proud of that 'please'. See, Professor Snape? Even in the face of provocation, a good teacher doesn't have to be rude.

A handful of rat tails landed on the table, followed by a paper twist containing … Hermione sniffed. Dragonfly thorax.

"Detention, Mr Aitkins, for the rest of this week. Return those to the storeroom, and see me after your last class today."

"Yes, Professor," he said sadly.

Hermione watched Colin like a hawk for the rest of the class, making sure he didn't go anywhere near the storeroom. He was, however, on his best behaviour — which did nothing to make her less uneasy.