Severus Snape's week rushed off his feet.

The Potions Master discovered that once he ignored Albus, dodged Umbridge and persistently failed to observe the existence of one obnoxious brat in Potions classes, he was able to lighten the heavy burden that rested on his shoulders.

Even the week of detentions which he assigned Potter in order to keep him out of trouble – and more specifically, out of Umbridge's office – was supervised by the portrait of an emeritus Potions professor. He was a vile man, which only partially explained why his portrait was usually stuck in a moldy corner in Severus' private labs.

And yet, when the brat had ceased from his habit to take a Brobdingnagian share of his time, his aunt took his place. To worsen the matter, she was kept under the surveillance of the only dog which Severus wouldn't hesitate to kick – Sirius Black. The impulse to “accidentally” kill the nosey horse-faced girl, one of his childhood hates, was restrained merely (or at least, that's what he told himself) by the fourth rule of Severus Snape: Never give up on an enigma.

The effect of magical potions and elixirs on Muggles was an untrodden research field, mainly due to the paper which was published almost a century ago, after a heated debate within the S.P.E.W. – Society for Potioneers' Ethics Worldwide.

Severus himself was one of the current members of the S.P.E.W.'s chief council, the youngest among them. His attempt to contest the decision of Muggle experimentation was thwarted by his reputation as a Death Eater. One of the leading voices, Holden Heatherfield, claimed that Severus' discernment in the subject was stained, and thus his preposition was rejected outright. It couldn't have been further from the truth – Severus saw the potential of inventing new medicines for the Muggle kind, saving countless innocent lives who died every year from avoidable causes.

But now, he had a willing patient before him and Severus was not the kind to give up on an intellectual challenge, let alone such a unique opportunity.

And finally – after a week of interminable research sessions in his laboratory – he held in his hands a concoction, an antidote to the Draught of Living Death, formulated under the principles of Muggle medicine and physiology.

Severus Snape hurried to the Headmaster's office. The old man raised his eyes to him, lifting one wrinkled hand as if to stop him. "Severus, I – "

Before Albus could finish his sentence, Severus had gone to the Order's Headquarters in a burst of green flames, through the only untracked floo in Hogwarts which wasn't covered with pink lace.

"Idiot, meddling old codger," drawled the dark man, walking out of the hearth. He climbed to the second floor, where Petunia Dursley dwelled. Her room was just as dreary as most of the rooms in Grimmauld Place 12, which was dullsville personified. It reminded Severus a little bit of Spinner's End – a house that happiness had no place within. 

His paces were muted due to a carpet which padded the whole corridor, one in the ugliest shade of brown that Severus had ever seen.

In spite of the size of the room, and perhaps due to it, the room seemed bare. A cream-white dresser, a huge glass cabinet and the same dreadful carpet were the only items there besides the four-poster bed.

Petunia Evans-Dursley was resting in the middle of all this 'beauty', and hadn't contributed a whiff to it. While her sister always added color to the places she had been in, Petunia seemed to suck it out; a Muggle parallel to the Dementors. Her constant need to be normal was an annoying obsession. It was the first time that Severus saw her without a sour, anxious mien – just a horse-faced, tranquil woman. She seemed almost normal and he felt his heart cleaving – the juxtaposition of this woman reaching peace, while her sister died in agony.

As he studied her peaceful expression, a low growl was heard. Before he had time to contemplate what was going on, his instincts acted for him. In an instant, his wand was seized from the holster and was clenched in his right palm.

"Put that down before you regret it," snarled Sirius Black from the threshold, mirroring Severus' posture, only with a redder wand. "What're you doing here, Snape? Came to inflict another dose of your slow-acting poison on Harry's aunt? If you try to hurt him, especially through something like this, I'll kill you." He raised his wand as if to prove the point.

Severus has found the notion of Potter shedding tears on his aunt's corpse dubious. A smirk appeared on his face as he understood that he had the upper hand on Black, and forever would; he knew something about Harry Potter that his godfather did not.

"Euthanasia of humans by potion is not something to refer so lightly to, Black," he answered as he returned the wand to its sheath, which was hidden inside his sleeve. Black wouldn't attack near Potter's aunt. Nonetheless, he kept the shield up, displaying his control over wandless magic. Black rolled his eyes.

"Snooty bastard." 

Severus ignored the comment and pulled a pair of sterile gloves over his hands, opening a set of syringes. "However," he silkily continued, "if I happen to encounter a stray dog… Abandoned by his family and friends… It is my public duty to help him reach quietus."

Black's face became a lovely shade of red. "At least I had friends to begin with, Snivellus. You never had any."

A slightly arched, skeptic eyebrow adorned Severus' forehead and he turned away. There was Lily, of course, and Black knew it just as well as he did. He crouched and rubbed an alcohol wipe over Petunia's jugular vein a tad harsher than necessary, leaving a reddish mark on her skin.

He would not drag Lily into this childish dispute.

"Why, your brother begs to differ," he settled, pleased to watch Black's shoulders tense up in the corner of his eye. "Dear Regulus, such a good boy. Unlike that Gryffindor brother of his…" Severus smirked. "Remind me, how many generations of the Black family were pure Slytherin before you arrived? Eleven, wasn't it?"

"Watch it, Snape."

The Potions Master's hands cupped the phial and he carefully uncorked it, filling the syringe with the orange, creamy-textured concoction. He diluted the antidote with a pump of salt, which was dissolved in the blood of a Panamanian white-faced capuchin.

"Such a shame to the family." He inserted the needle into Petunia's vein, pumping boluses of the matter into her blood system. "And it goes, of course, without mention, twelve years in Azkaban…"

A stiff hand gripped his shoulder harshly. He jerked, slightly.

"Sit down, Mutt,” he ordered, amusement in his voice. “I wouldn't want to mess up and accidently hurt your precious godson's aunt." Black had no choice but to release him.

"Careful, Snape." The other man revealed his teeth. "I wouldn't want to mess up and accidently justify my time at Azkaban."

"As if you'd get me." 

Severus removed the syringe carefully and put it down. He turned around and drew his wand, surprised to see that Black didn't, despite his heads-up. Instead, the other man snatched Severus' wand from his hand, throwing it to the other side of the room. Severus' silent Accio caught it midair and he raised himself from his position. He loomed above the other person, using his few extra centimeters as an advantage.

He gripped Black's right wrist and pulled it upwards, forcing the man to straighten up. "Bad dog. That's not how you play fetch," he purred, close enough to smell Black's breath. "I hope you don't teach your godson such bad habits."

He met a murderous expression. "Stop going around, Snape! Leave my godson out of it. We knew it would happen since the day we met." He paused to swallow, and continued harshly, "If you are a man, duel me."

"Very well." Severus agreed – suspiciously quickly, releasing the other man's wrist. The Gryffindor tried to put a little distance between them in order to curse him, but the taller man wasn't a sly Slytherin for nothing. Before Black could analyze his willingness to duel, he swung his upper body and punched Black's nose.

A sickening noise was heard as it broke. Severus smirked, but the satisfaction hadn't prevented him from kneeing his rival's guts. Black fell to the floor in a fetal position, groaning and holding his bleeding nose with two hands. Red dripped to the dull brown carpet.

"If you were a man,” he hissed in a silent whisper, “You'd have gone one on one with me instead of bringing your cronies along. But we knew it would never happen, since the day we met." His boot crushed into Black's ribs and his eyes gave Petunia Evans-Dursley a last glance as he packed his belongings and exited the room. If everything went well, she'll be awake in twenty-four hours, presumably complaining about the stain of blood on the carpet.

He stopped at the living room to scribble a note, where he recommended Albus to check on Petunia the next day. Despite the improbability, he couldn't help but hope that Black wouldn't last so long. He thrust the parchment into Albus' hands as he crossed the Headmaster's office as fast as he could, his robes billowing. The statue of Nott Sr. glared at him from the corner, covered with green and orange neon lights, and Severus' lips quirked for a moment.

But only for a moment.

On his way to his personal quarters, suddenly feeling lighter than he had been for months, Severus heard a fragment of a conversation that piqued his curiosity.

"… How many times do I have to explain it to you, Ron? S.P.E.W. is an important organization!"

So, Granger knew about the S.P.E.W.? Interesting. Severus stopped before the turn, listening.

"Well, it isn't as important as the D.A., right? So why don't you just drop the matter and – "

"Guys, calm down!" Potter. "It doesn't matter which one Umbridge banned, the important thing is that she banned both of them!"

Severus paled. Umbridge banned the S.P.E.W.? Oh, this cannot be good…

"It certainly matters!" Weasley. "Who cares about spew, anyway? It's just a stupid organization with no – " Severus had enough, and he strode past the corner with a thunderous expression.

"For your knowledge, Mr. Weasley, the S.P.E.W. is a salient organization which accepts only the brightest witches and wizards into its service. You, for example," he glared icily at the redhead, "won't ever be a part of it."

Severus crossed his hands over his torso and leaned on the stone wall, allowing a smirk to conquer his expression. The members of the Golden Trio gaped at him, and Weasley's ears became red. As usual, Granger was the first to recover.

"Sir, I didn't know that you were familiar with S.P.E.W.."

Severus snorted disdainfully. "Daft girl. Of course I'm familiar with S.P.E.W.!" How could he not be? Every Potions Master who respected himself and position knew of it.

Before any of them had time to respond, Severus continued. "I am, in fact, one of the members of the chief council of S.P.E.W. for the last two years." He stole a glance at them; they all looked puzzled, and Severus was smugly proud of himself. He picked his nails, pretending to not notice. "After all, I do rank second place in Europe for Potions Masters with the largest number of citations and published articles."

Granger's mouth caught the shape of an O, and her male companions had the audacity to stifle a laugh. "Detention, Weasley, Potter! Report to Filch tomorrow at six am, before breakfast." Both of them lost their smile. Weasley seemed horrified at the concept of getting up so early. "Twenty points from Gryffindor for blunt disrespect towards authority figures." He passed them, giving Potter's shoulder a harsh squeeze, only stopping when he reached the end of the corridor. "For each."

There you go, Severus, he cheered inwardly. More time in detention, less time to find trouble.

Harry and Ron stared at Snape's back, dumbfounded, as Hermione suddenly began to chuckle.

"Did Snape just assign us a detention because you mocked Hermione's club? And admitted that he was a member for two years?!" asked Harry, trying to understand what happened. Then, he turned towards Hermione, incredulous. "And you haven't told us that you got Snape to buy your badge? The flowery, red badge?!" Hermione only laughed louder.

"Oh," she said, wiping a tear from her left eye after she laughed for a whole minute straight. "S.P.E.W. is also the name of the ethics committee for Potions. Karma is a bitch, Ronald."

Harry couldn't help it, and despite the fact he had just received an unjustified detention, he joined her laugher. Ron kept trying to figure out what the hell was Karma, but soon he gave up on extricating any answer from the amused pair and joined in himself.

After a few minutes, the laugher trailed off.

"I wonder what happened to Snape's left knuckle," Hermione noted, her tone sobering up. Ron's brows wrinkled and Harry glanced at her, surprised. "Didn't you notice? It was bruised. Freshly bruised, even."

Harry's gaze dropped to the floor, when he saw it.

"It must have been a really fresh bruise," he told her, crouching closer to the floor. Both of his friends stared at him. "How do you know?" Hermione asked as they crouched next to the dark-haired boy. She gasped when she saw what was imprinted on the stone floor.

"Because I happen to wonder what happened to Snape's boot," he answered in an ominous tone. They peered at the red pattern that the boot left on the grey floor.

Abruptly, Ron smiled. "I happen to wonder what happened to your shoulder!" he exclaimed, fishing a note that was stuck to Harry's left shoulder. Was it from Snape?

The writing confirmed his hypothesis – written in spidery small letters, the message was concise, but vague:

The female whale is in capable hands.

Hermione looked at the note, reckoning, but for once both Ron and Harry were ahead of her. After all, the message was crystal clear for those who knew both the Dursleys and Snape, who wouldn't call anybody capable but himself –

I'm taking care of your aunt.

The note caught blue flames while it was in Ron's hands and he dropped it. By the time the parchment hit the floor, only ashes were left, carried away on a light breeze blowing through the open window.

After seeing the animosity and malice that Vernon held towards Snape – and surely, Petunia was on the same page as him as him – Harry wondered what reason the Professor had to bother at all.

And really, wasn't it strange, that the words which were a threat merely a fortnight ago were now considered a reassurance?

Ron echoed his thought aloud. "Snape is a git. He's probably trying to imply that he's going to poison your aunt. Not that I have a problem with that, of course…"

"A little respect won't hurt you, Ron. Professor Snape is not very nice, but he is one of the top Potions Masters in the world. I'm sure he's able to deal with anything that the Death Eaters have done to Harry's aunt," Hermione admonished.

"Well, maybe he had a hand in it!"

"Ugh, Ron!" Hermione sighed impatiently. "Even if he wanted to hurt her, surely Professor Dumbledore – "

"Dumbledore is too much of a goody boy, Hermione! Can't you see it? Snape's using him to – "

Hermione spluttered. "Goody boy?!"

"Yes, goody boy!" Ron repeated, stubbornly. The tips of his ears became even more flushed. "If you can call Snape a 'not very nice' guy instead of 'the biggest git alive', I get to call Dumbledore a goody boy!"

Harry settled his hands over their shoulders, shutting them up very efficiently. "Snape is nice where it counts." He remembered the time when Snape supported him on the way from Umbridge's office and when he rescued Harry from his flashbacks about the Dursleys. He thought about the time when Snape punched Vernon, or defeated two Death Eaters. Well, he also helped Harry fix his potion after he destroyed it, but it was for a good cause, so it counted too. And that one decent Occlumency lesson with drunken Snape. Or the fact that he hadn't smacked Harry and didn't even deduct points when the boy asked him about his greasy hair.

Not to mention that once upon a time, that git was his mother's best friend, a wise boy with a sharp tongue.

Snape was not a nice guy, by all means, but sometimes he could be…

Decent.

"And this argument ends now," Harry summed up, pleased to place a new title on Snape's head.