When he was meant to leave the next morning for school, his stomach laden with leftovers from the night before, Harry was surprised when Severus accompanied him out the door and directed his course toward the car.

He was miserly with explanations when Harry asked the man what he was about, and rather than giving any sort of satisfactory answer, responded with impatience.

"Am I not allowed to offer you a lift into town? If you'd rather leg it yourself, I welcome you to follow behind in the exhaust cloud."

"There's no need to be mean," Harry muttered, buckling himself into the backseat beside his school bag.

"There's no need to ask about things that don't concern you. There's a saying, Potter: don't look a gift horse in the mouth."

Harry, who was kicking his legs as he often did on car rides, purposefully allowed one of his feet to bump against the back of Snape's seat.

"So, if some man comes up offering candy I should take it, no questions—"

"Don't be dim, of course you ought not ask questions! You run your scrawny arse out of there and come find me."

Dearly wishing he could make a point about how Snape had once been the same manner of stranger to him, and a housebreaking one to boot, Harry nonetheless managed to button his lip, though he did kick out at Snape's seat once more for good measure.

"Do not tempt me, Potter—" Snape growled, reaching back a hand to swat ineffectually at thin air, where he perhaps approximated Harry to have been sitting.

"I'm not—"

"We'll see if there's anything left of the bibingka by the time you make it home this afternoon."

As far as threats went, it was a relatively weak one, which Snape seemed to know from his frown. As much as Harry was hoping for another helping of rice pudding, he'd gone without food—and without sweets in particular—far too many times to be cowed by such a punishment.

When he ceased antagonising Severus it was merely because he'd decided the other wizard had likely suffered enough for one morning.

And besides, it was rather nice that he'd driven him in to school.

The ending notes for Saxon's Denim and Leather were ringing off when Snape reached over to depress the pause button, his hand on the wheel causing the tyres to swerve to the left a bit as he leaned towards the passenger seat.

When they came to a full stop, Harry had to forcibly remind himself to unclench his teeth.

He exited the car and walked towards the doors, only to hear another slam behind him as Severus left the car in the drop-off lane.

Harry felt his eyes widen as Severus approached, his face set in a forbidding, black scowl.

"Did... did I forget something?"

"No. Go ahead to class, Harry."

"Then, erm... what are you doing still here?" Harry asked, walking in step with the older wizard through the foyer. "Er... I don't think you're meant to park there..."

Snape snorted, the reaction so violent that Harry was surprised not to see two twin bursts of air issuing forth from the man's bull-like proboscis. "They won't have anything to say to me over it; don't worry your messy head. Now, don't be late," he reiterated, turning Harry around by the shoulders and giving him a gentle shove down the hall.

He didn't dare to look over his shoulder again, even though he was far earlier than he'd been the day before thanks to Severus' Morris Marina.

When Harry arrived in Mr. Fowler's room, he was one of the only students to be seated with the exception of one boy who always sat at the very front of the class.

For lack of anything better to do, Harry went about extracting his pens and pencils from his bag, taking pains to line them up in an even line of ascending size as he's often seen Severus do with his knives and potions tools.

When he was finished and still saw five minutes on the clock, he went about spacing them so each had a uniform three centimeters separating them, and then—when this too failed to take him to the bell—he began to even them up on the bottom until the erasers were all in order.

When lessons were supposed to begin, Mr. Fowler wasn't yet in evidence, and the class quickly descended into loud whispers and gossip. A couple of girls in the middle formed up a circle and traded scraps of paper, giggling behind their hands, and another girl who always sat near the back, alone, had folded up a paper aeroplane and sent it flying above the heads of the other students until it dove, nose first, onto the teacher's desk.

The footballers, who always sat in a pack near the centre of the room, were busy discussing strategy and the last World Cup, though for reasons that Harry couldn't fathom, Nicky Henderson sat a bit back from the others, his arms crossed as he leaned back on the rear legs of his chair. He appeared troubled.

Snowdrop Hill hadn't come in that day.

Another few planes joined the first before Mr. Fowler rushed into the room, his hair flying about.

Had he his wits about him he might have tried to take the students to task over the small fleet of aircraft that had made their roost on his desktop in his absence, but as it was, he merely swept them aside after a cursory look, allowing them to scatter to the far reaches of the classroom.

While he set about introducing the day's lessons to his students, Harry noticed that Mr. Fowler's eyes didn't leave him once. Their teacher was practically staring daggers at him—although he didn't necessarily appear angry, and he didn't once single Harry out.

About halfway through the morning lesson, Harry heard raised voices out in the hall—the loudest of which sounded like it likely belonged to Mrs. Murray, and he could have sworn he heard Severus' voice, though it wasn't raised. If anything, it sounded like that slick, oily tone he liked to use when he was dealing with people he found particularly lacking in wit.

There were a few other people who spoke, but it was impossible to tell who they might have been, and as soon as the argument—for it must have been an argument from Mrs. Murray's tone—started, it was over, and Mr. Fowler's own droning lecture papered over whatever may have occurred.

It was the first normal week of school after the hubbub that always came with the week term resumed, and that meant that after the break and lunch, their class had the first of their twice-weekly music lessons.

On Tuesdays and Thursdays they were meant to have an hour of musical instruction. On Wednesdays, Harry was given to understand that they would take an hour in the morning for art. And on Mondays and Fridays (which had been skipped the day previous for reasons particular to Mr. Fowler's lesson plans), they apparently were to repair to the gymnasium for physical education, which had always been Harry's least favourite, as in the past it was always the class that Dudley had had the easiest time tormenting him.

They were ferried to the music room that was on the far end of the school by Mrs. Murray—who was also throwing dire looks Harry's way, although she didn't deign to say a word to him—and they all took seats in the chairs which were arranged in a three-quarters circle that was capped off on the far end by an upright piano.

It was tall enough that it hid the presence behind the keys from them until the door shut behind the last student into the room.

That was when a teased-out mess of crimped blonde hair poked up from behind the piano and chirped a bright, bird-like hello to the circle of students.

The hair belonged to a spritely woman of perhaps twenty-five, who rose from her piano bench to write her name on the blackboard in chalk that was of an alarmingly pink shade.

Ms. Tabitha Tibbons

She took a moment to brush the chalk dust from her tiny hands and then clasped them in front of her, casting about for a moment and looking unsure of herself.

"How many of you enjoyed your classes last year with Mr. Hargrave?"

A few hands went up, and Ms. Tibbons nodded, the motion of it sending her floofy fringe flying in all directions. "He'll be dearly missed. He was my music teacher while I was here too. Did he work with you all on rhythms?"

Some of the students nodded and the same boy that had sat at the front of the class when Harry first arrived that morning raised his hand.

"We did rhythms ages ago, Ms. Tibbons. I want to learn scales—"

"I'll ask you wait to speak until you've been called on, thanks, Mr...?"

At least the boy had the good grace to dip his head as he blushed, his hand being yanked down once more to his side. "Jack. I'm called Jack."

"Jack..."

"Sandys."

"Yes, well—Mr. Sandys, I appreciate you letting me know what you've been up to. I think you'll find that a sense of rhythm is important even to the most accomplished musicians, and that practising it often is more helpful than a waste of time." She held up a box full of blue, foot-long sticks. "Everyone take a pair and pass the box along, please."

Approaching the edge of the circle, Ms. Tibbons held the box out to a boy who Harry thought might have been called Carl, although he couldn't quite remember. She stood back with her foot tapping some unknowable beat as she waited for the box to make its way around the circle.

They practised a few different beats with the sticks, and Harry had to continually suppress his urge to wave it around like Severus' magic wand.

It was incredibly boring, and he, along with several other distracted students, had to be called to order more than once.

Clearly, she was new. No one seemed to know her, and she hadn't yet figured out how to keep the attention of her students beyond the first five minutes of class.

She ended before the hour was up and collected the sticks into the box once more before the class was instructed to go by turns announcing their favourite musicians and why they liked them.

Ms. Tibbons had pulled up her piano bench so she could sit in the small hole at the edge of the circle, pointing to each of her students in turn with a spare drumstick, wielding it like a conductor's baton.

"Blondie," one girl had announced, and, fingering her own head of limp brown locks, she explained that she was envious of Debbie Harry's iconic hair.

"I like Mozart," Jack Sandys announced, turning his nose up in the air and affecting a superior tone of voice.

"I love Mozart!" Ms. Tibbons agreed, nodding her head and sending her over-processed hair bouncing. "What's your favourite piece by Mozart?"

This brought Jack up short, and he blinked rapidly, apparently having a difficult time naming anything on demand.

"Er..."

"That's alright! Why do you like Mozart, Jack?" Their teacher asked, obviously offering the boy an out.

"Well, 'cause he's a genius, isn't he?" Jack asserted, sounding almost combative.

"Erm—yes. He's broadly considered to have been a genius... very good, Jack, thank you."

Next came Nicky, who was seated beside Harry himself.

"Mr—"

"Henderson," Nicky supplied, grinning a bit. "I'm Nicholas Henderson."

"Very good," Ms. Tibbons said again. "Mr. Henderson, who's your favourite?"

"I like John Williams. He's the one that did Jaws and Star Wars."

"Oh, that's a great choice!" Ms. Tibbons began to gesticulate with her hands to illustrate the list she was continuing calling out names of films that Harry had never before heard of before she finished with: "He's responsible for so many! Probably most of our favourite films in the past ten years have had John Williams as a composer; I'm glad you've mentioned him."

Nicky looked rather pleased with himself, and Harry felt his mood tank at the sight of it, which was odd. He didn't necessarily hate Nicky, or even dislike him too much... but Harry had only heard music he liked or would have called good for the first time in his life two months ago. Nicky seemed like the type of boy who was up on everything new, if his questions about films the day earlier could provide any context. He seemed to take pride in his ability to be conversant in culture.

Harry couldn't claim to be able to do the same.

He liked, for the most part, what Severus liked. And before that, he'd been familiar with the records that his aunt had been partial to, even though he'd never developed an appreciation for her tastes himself.

For the first time in his short life, he actually felt lesser somehow—at least on his own, and without the addition of his relatives' constant criticism which he'd only taken halfway to heart—and he wasn't at all sure how he was meant to cultivate his own palate as far as popular culture was concerned.

When he'd decided on what he was going to name, he had been excited to share... now he found himself feeling sheepish as Ms. Tibbons gaze moved to rest on him, her slightly protuberant eyes blinking at him in quite the way a neotenous bunny rabbit might have.

"I... erm..."

"Start with your name, if you please."

"I'm called Harry. Potter. Harry Potter." Harry began, taking a deep breath as he saw Ms. Tibbons nod at him with encouragement. "And I think I like David Lee Roth best..."

It wasn't necessarily true. He'd meant to talk about how he'd very much begun to appreciate Van Halen, but had changed it at the last second, thinking on how Severus didn't seem to care as much for David Lee Roth as a front man as he did for Sammy Hagar... and Harry had to start forming his own opinions on things at some point, hadn't he?

David Lee Roth was the one who'd paired up with that frighting Steve Vai from the movie he'd watched in hospital, and as far as Harry could say, there couldn't possibly be anyone more talented on guitar than him, if the movie could be trusted.

There wasn't anything so very wrong with Hagar, in truth. Harry liked 5150 well enough as an album... but on the rare occasions where Severus had instead played one of Van Halen's older albums with Roth as the front man, Harry remembered thinking that the band had seemed to have a wholly different flavour to that of their current artistic direction.

It had seemed to him more brash, more bawdy, just... more. Of everything.

The guitars had been louder, and Roth's wailing had been wilder, the tempo was faster, more up-beat... it'd had Harry straining to keep himself from bouncing on his heels, which he just knew would have gotten up Severus' nose.

For some reason, his choice had Ms. Tibbons blushing, the colour of her face clashing terribly with the very pink shade of rouge she'd selected for her cheeks that morning.

"He's... oh. Yes, he's very talented," his teacher agreed, twisting her mouth in a strange half-smile, half-grimace. "I don't suppose you have a favourite song?"

Harry was just about to name the song with the most mind-blowing drum solo he thought he'd ever heard—at least to his inexperienced ears—when he remembered the name of the track and thought better of it.

No. He could not tell his pretty, blonde music teacher that his favourite Van Halen song was Hot for Teacher. That wasn't on.

If possible, the song he ultimately named may have been a worse choice.

It preceded Hot for Teacher on the track listing, being the last song on the first side of the tape where Hot for Teacher was the first song on the second side.

"Drop Dead Legs."

He felt his face light up with embarrassment as soon as the words left his mouth. Worse, Ms. Tibbon's face had gone a deep maroon and she'd ducked behind her hand to cover for a sudden fit of coughing. As soon as she was able, she pointed her drumstick at the girl next to him and demanded that she continue on in the same fashion as those who'd come before her.

"Lucy Givens... I really like David Bowie a lot,"

And so it continued until the final student had had her say, and Ms. Tibbons lined them up to exit her class and to follow the hall-minder back to Mr. Fowler's room.

Little else happened of note during the second half of the day, and near the end, Mr. Fowler handed them a stack of maths papers each that he expected to be returned the next morning, filled out with their equations, written long-hand.

It was with great relief that Harry packed up his bag to leave and fled from the classroom. He was one of the first out of the doors, pointedly ignoring the way that Nicky Henderson was waving for his attention.

He bolted down the hill, feeling as though he may well pitch forward and roll the whole way down, and was barely winded by the time he made it half-way over the bridge.

It was only then that he allowed himself to catch his breath, coming up to the concrete wall that protected motorists and pedestrians from falling over the side. He looked out on the violence of the river below, watching as a few salmon jumped up from the churning waters.

The encampment of homeless were occupied as they had been the day before, and Harry watched with mute fascination as their dog waded into the shallows and snapped ineffectually at one of the jumping fish, leaping back when the salmon fell back into the waters and splashed water on its grimy muzzle.

The beast whined loudly enough that Harry could hear it where he stood on the bridge, and the tramp stomped over to it, waving his fist at the dog and yelling in the incomprehensible dialect that was apparently the unique specialty of Backbarrowers.

Behind him, he heard a set of tyres screeching to a halt and he jumped, nearly catapulting himself over the side of the bridge in order to avoid being hit.

He needn't have bothered. The pavement was wide enough that unless a car had purposefully pulled up onto the kerb, there was no way he was in danger, but Severus' warning to him about strangers still rang loudly in his memory.

Lucky for him, it was Severus himself who leaned out of the driver's side window and was hailing him over to the door.

"I waited for a quarter of an hour for you! Why did you leave school?"

"Wasn't I meant to?" Harry asked, jogging over to the car. He had to go around and carefully check for traffic before he opened the passenger side door and squeezed behind the seat, throwing his school bag onto the bench beside him. "I thought I was supposed'ta walk home like always—"

"I wasted my whole damn day at that mouldering heap and stayed an extra fifteen minutes past when I could have left to offer you a ride back to the house. That'll be the last time I go out of my way," Snape groused, sounding rather grumpy, even by Snape's standards.

"Sorry, Severus." Harry ducked his head as Snape turned the volume knob on the tape deck up once more. It was only a five-minute drive to the house, but evidently he didn't plan to spend the time sitting in silence.

"Why were you at school all day?" Harry asked as he watched the boarded-up buildings and empty lots pass them by through the window.

In response Severus gave a mighty snort and when Harry looked up to the rearview he saw the man rolling his eyes in annoyance. "I may as well tell you, I suppose. No doubt you'll hear about it somehow."

"You don't have to..."

"Of course I don't have to! I thought I might do you a favour. Perhaps, at that, I'd be doing myself a favour by telling you."

Snape took a moment where he gnawed at the fleshy part of his lower lip, his jagged front incisors looking as though they may well rip a hole in his skin if he kept at it much longer.

Finally, his tongue darted out to lick at the spot he'd worried raw, and his upper lip lifted into his familiar sneer as his eyes swept the street in front of him.

"I was in a meeting for the better part of the day with Headmistress Shaw—"

Harry's eyes widened behind his glasses. "Am I... am I in trouble?"

"No. Don't interrupt again," his guardian snapped, glaring at him through the rear view. "It was enough of a nightmare to endure the shrieking of that demented banshee and the ineffectual bleating of your milksop teacher."

"Mr. Fowler?"

"Yes, him." Snape's hands tightened on the wheel and shifter until his knuckles were the colour of slightly spoilt milk. "He ignored Miss Hill's symptoms until it was nearly too late. A pitiable lack of classroom control from what I witnessed when I arrived—"

"How did you know to come anyway?"

Snape seemingly had forgotten his proscription against interruption, for he answered without another cross word sent Harry's way. "Credit me with a bit of sense, Harry. In addition to telling me where you are at any given time, your lapel pin also tells me when you're frightened. Miss Hill's condition caused you to panic, so naturally I came to see if you were in danger.

"This morning it was myself, your teacher, and the headmistress. That might have been OK if that interfering harridan hadn't pushed her fat nose in where it doesn't belong—"

"What's a Harry-Dan?" Or could it have been a 'Hairy Dan?' Perhaps in the same vein as those strange five-legged creatures Snape had been telling him about a few weeks earlier...

"A bitch—" Harry thought he heard Snape mutter under his breath and then more loudly the man elucidated, "An unscratchable itch. A pain in your backside. Namely, a very loud, very annoying woman."

"Ohh," Harry nodded his understanding. He knew all about that type. That was his uncle's sister—his not-Aunt Marge—to a T.

"And here I thought I'd seen the last of her when I left for Hogwarts," Snape shook his head so his hair flew about his face like vines. "You owe me, Potter. I never thought I'd have to see Mrs. Murray again, and I only have to suffer her now because of you."

Harry winced. "I'm sorry," he told the man, actually meaning it. He didn't care for that woman at all. If that's what a 'harridan' was, then Harry found he could quite sympathise with Snape's irritation.

And it was no secret at all that Judith Murray hated Severus Snape for all that she was worth, although Harry couldn't even begin to guess at her reasons for it. By his accounting, Snape was alright. And likely, Harry had more reasons he could have hated Snape than most, from what the man had confessed to on the ride back to Surrey months before.

In fact, Harry would go so far as to say he genuinely liked the prickly grump, in spite of everything he'd learned.

"She didn't even have anything to do with it," the man complained, grousing aloud and not really to Harry in particular. He punctuated his grievance with a thump of his palm against the wheel. "Just barged her way into our meeting without a by-your-leave."

"So that was you I heard in the hallway? I thought there was shouting,"

"I wasn't shouting. Judith was shouting," Snape corrected, his voice snide and pedantic all at once. It seemed he didn't quite know what to call the woman, given that she was many years his senior, and he'd known her since he himself was a boy. It was clear he didn't respect her in the least, and given that she wasn't a man, he didn't seem inclined to call her by her surname. Thus, it seemed he'd settled upon using her full Christian name, probably out of spite.

Harry had to grant that of all the possible choices, calling her 'Judith' to her face likely would have annoyed Mrs. Murray the most.

And although the man could have possibly taken it a step further if he'd chosen to call her 'Judy,' that almost seemed too playful to suit Snape's style.

"And anyway, Headmistress Shaw finally told her to take a hike, but only after Miss Hill's grandmother arrived. Until she was ousted from the room, nothing productive was accomplished, in any case."

"Why didn't Hill's parents come?" Harry asked. "Or is she still in hospital? Are they with her there?"

"Miss Hill is recovering at home, and you likely won't see her until the end of the week. As I understand it, her parents are out of the picture."

"Oh... she's like me, then?"

Harry saw Snape's shoulders rise and fall in a shrug as he pulled the car up onto the kerb outside of his house. "I couldn't say. I didn't ask. You see, Potter, generally speaking, it isn't politic to go about asking invasive questions where it's not one's business to do so."

The boy ignored the slight as he crawled out from behind the driver-side seat that Snape had pulled forward for him, reaching back to snatch up his bag before slamming the door closed.

They entered the house and Harry sat against the wall, pulling his trainers from his feet while Severus sat upon the couch and did the same with his boots. They both lined their shoes up against the wall beside the door, one large pair next to the tiny one.

"Have you any homework?" Snape asked, rising from the sofa and heading for the kitchen. Harry jogged after him and dumped the contents of his bag onto the rickety chair, given that the table was entirely occupied by cauldrons and cutting boards.

"Just some maths stuff," Harry wrinkled his nose.

"And how are you with that?" Snape asked, pulling out a mortar and sprinkling some hard, wrinkled, peppercorn-like balls into its belly. (Harry only knew they weren't peppercorns because they were a bright orange). Snape then grabbed for a stone pestle and got to work crushing them underneath its weight.

Shrugging, Harry pulled the worksheets out. "I'm ok with sums," he answered honestly, "but we're working on multiplication, and I got lost when Mr. Fowler added in the tens column."

"Sit here while you work." Snape told him, hefting one cauldron over so that there was a tiny space available. "I'll check your answers over after you've finished."

Harry pulled a pencil from his bag and sat at the table, leaning over his worksheets as Snape worked at preparing a long list of ingredients that grew more bizarre and outlandish as he went on. In the background, he'd set the tape deck to playing Dokken, although softly enough that Harry still managed to hear himself think.

He managed to get to problem number ten before he became well and truly confused.

Scratching at a cowlick, he glanced up at Severus. The man was frowning down at a scrap of parchment, one stained fingertip tracing down along a hand-written list as his other hand was popping seeds from a pod like little zits.

"I think I'm lost."

"What's the problem?" the older wizard asked without looking up.

"Erm... it seems to me that the number couldn't be this low?"

"No, Harry, what is the actual problem. Give me the numbers."

"26 multiplied by 12?"

"Show me how you've done it then," Snape demanded. He snatched the cloth from his apron pocket and used it to wipe off both of his hands, edging around the table until he was peering over Harry's shoulder.

"What—" Snape scoffed and grabbed the paper. "What are all these marks in the margins?"

"It's the first number, see? There's twenty-six—"

Harry glanced up to see that his guardian looked bewildered. "Why've you done that?"

"Well, I thought I'd get the answer if I counted the ticks twelve times..."

"Is this how you've done all of them?" Snape asked, his eyes rounding as his lip curled in a dumbfounded expression. He was now checking up the side of the paper where Harry had, indeed, been making tick marks for each number he was meant to be multiplying.

"Yeah, it's easier—"

"It isn't! And clearly you've lost count a couple of times. You're off on most of these answers... did that teacher of yours not explain how to work columns for multiplication?"

"He showed us," Harry objected, twisting his pencil between his fingers, "but I didn't understand what he meant really..."

"And you didn't think to ask?"

Harry ducked his head and didn't say anything. Didn't want to mention how it was that he'd avoided asking questions in class for years because, simply put, having better grades than Dudley came with its own share of punishments.

It had always been simpler to keep his head down and to avoid trying too hard.

If he prevailed over his cousin, it would mean Aunt Petunia barging into the head's office and fighting over how the grading was unfair, along with accusations that Harry must have been cheating. To simply allow himself to fail meant that he'd endure endless crowing over how much cleverer Dudley was—but in truth that was a small price to pay for Harry's peace of mind.

"Can you explain it?" Harry said instead and handed the pencil over.

Snape grabbed a spare bit of parchment and sketched out a few new equations with different number sets than the ones on the work sheet.

"We'll work these as practice; I'll not be doing your work for you. Then you'll need to do numbers 2, 5, 7, and 8 over again. They're all wrong."

Together they bowed their heads over the parchment as Severus explained, with surprising levels of patience and fewer insults than he'd been expecting, how Harry was meant to multiply larger numbers, using what he understood of his memorised multiplication tables. When the boy reapplied himself to the worksheet, he managed all but two of the twenty problems correctly, and when Severus pointed out to him where he'd made errors, he managed to correct them himself without Snape providing the answers for him.

"Have you any more work for the evening?" Snape asked him after as he watched the boy stuff the papers back into his bag.

Harry shook his head, no. "Can I help with ingredients now?" He asked, his voice hopeful.

"You may sit and watch, but I don't want you touching anything."

At Harry's crestfallen expression, Snape sighed and got to work, though he did explain himself. "These are highly allergenic. Nearly half of the wizarding population has a reaction to them and it can get quite nasty. I know I can touch it with my bare hands, but I'd prefer not to test your tolerance."

"Oh."

Harry watched, his legs drawn up on the seat of the chair so that he was kneeling on it with his hands braced on the tabletop as Snape continued to pop the strange pods. They wept green goo all over his fingers and Harry had to wince.

He had a high threshold for disgust, which helped him a great deal whenever Severus did permit Harry's assistance, but this was pretty gnarly. Even Snape's face was dangerously close to a grimace as he deposited the tiny pea-like contents of the pods into a red-clay dish.

"What are they?" Harry asked. The peas rolled around the dish on their own, pinging and ponging off of one another in a chaotic, unpredictable sequence.

"Pyrenean magigrano," Snape answered, managing to catch one pea in his palm as it spat out of the pod towards Harry's face. "I'd not say they're highly dangerous or anything, but under normal circumstances, most brewers would buy them already processed from an apothecary."

"You're doing it yourself to save money," Harry guessed, feeling his heart sink. He was costing Severus so much... before Harry had come along, Severus had had a good job—

"I'd be doing it myself regardless," the older wizard refuted, his mouth set in a grim line. "I don't care for shortcuts in potioneering. Anything worth doing is worth doing yourself. I saved Hogwarts thousands of galleons since I started by either doing my own processing, or by assigning the task for detentions.

"Besides saving money, it assures freshness, and also the integrity of the ingredients. When you buy magigrano from Slug and Jiggers, they've dried the peas. Who knows when they were dried? Or whether the method they used allowed for mould contamination. And while the uses for the sap and the pod itself are uncommon, I'm not one for waste."

Harry eyed the pods and the pus with a new appreciation. "What if that's what you need for your new thing?"

Snape smirked a bit as he caught another pea, allowing it to fall from his fingers into the dish. "That's rather unlikely, Potter, but you're thinking on the right track, at least."

"Can't I do anything to help?" the boy asked, frowning as it came out as a bit of a whinge.

The man paused what he was doing for a moment and then pointed his slimy finger toward a medium sized cast-iron cauldron he had sitting by the sink.

"You can dispose of that for me. It's inert, so it oughtn't harm you, but it's resisted being vanished."

Harry approached the cauldron with some trepidation and used the wooden stirring rod to lift a bit of the ruined potion out for inspection. It was black and tar-like, fighting being raised from the belly of the cauldron and dripping down in ribbons—as molassas might have—off of the stirring rod.

Upon closer inspection, Harry saw that the actual potion itself was nearly colourless, but that it contained vast amounts of isolated black particulate within its matrix, rather like used engine oil.

"If you can't vanish it, how am I meant to dispose of it? Down the drain?"

"Don't you dare!" Snape called over his shoulder, and when Harry turned at the shout he saw that the man was glaring at him with a forbidding expression. "It'll ruin the pipes."

"Then how—?"

Snape stomped over to him then—a feat impressive for the fact that the man wasn't wearing any boots—and yanked the cauldron from the counter, he beckoned to Harry that the boy ought to follow him out the back door.

It was no fun trudging out into the dirt in his socks, but Snape himself was doing it, so Harry followed suit and watched as his guardian fetched from the far end of the garden a bin that Harry had always assumed to be an extra rubbish pail.

When Snape lifted the lid and Harry was able to peer inside, he saw that it may as well have been a well: it seemed as though it could go on forever, which ought to have been impossible given that if Harry pulled away from the pail's mouth he could see the bottom of it sitting, neat as you please, on the dirt of their back garden.

"... how—?" Harry asked again, his mouth hanging open as though the hinge of his jaw had broken.

"Magic." Was Snape's terse response. "Scoop out as much as you can into here and when you're through with that I'll find you the potion degreaser and you can scrub the cauldron. Make sure you put it on the cooker to dry with the hob on low or the water will rust it."