When he wanted to see me, Dumbledore would usually firecall me to his office, or Floo to mine. But today, he said, go to 12 Grimmauld Place, and wait in the kitchen. I could guess why, but hoped I was wrong.

Unfortunately, I'm rarely wrong. To my utter lack of surprise, Sirius Black was in the kitchen already, sitting at the end of the table. A copy of the Daily Prophet was in front of him, opened to the crossword puzzle. I was also not surprised to see that Black was not alone. Tonks sat in the middle chair, her hair some revolting colour I couldn't name. Puce, maybe? As I entered, Black was smiling at her in a highly inappropriate way, considering the girl is his cousin. He looked up at me and stopped smiling, then stared back down at the newspaper.

"Tea, Severus?" Tonks asked, lifting a teapot. "I made it fit to dissolve a spoon."

Who told her how I like my tea? Dumbledore usually respects my desire for privacy.

I glared at her while she poured a cup and somehow managed to hand it to me without dropping or spilling it, meeting my glare with a cheeky grin. "I don't need an Auror to protect me from Black. At least, not lately." I sipped from the cup. I like my tea strong enough to permanently stain my teeth, so this tea was perfect. Not that I was going to tell her.

"Maybe there needs to be an Auror to protect Sirius from you," Tonks replied.

"Hey!" protested Black eloquently.

"Dumbledore trusts me," I retorted.

Black snorted. "Nobody's perfect," he muttered.

Immediately I restrained myself, unclenching my right hand and removing it from a particular pocket. Tonks was there, after all, not just to make sure we didn't hex each other, but as an observer. She would observe me, and see a picture of restraint.

She would observe Black, and see what I wanted her to see.

I walked casually around the table, opposite to where Tonks sat watching me avidly, and looked down at the crossword puzzle in front of Black.

"Thirty-six down is 'Snorkack.' Obviously," I said. Mindful of Tonks' presence, I was trying not to smirk too broadly.

Black's years in Azkaban have left him teetering on the brink of insanity, but he's not as stupid as he looks. He glared at me for a moment, then forced himself to stay in his seat and look back down at the crossword.

"Doesn't fit," he said in an extremely quiet voice quivering with suppressed anger.

"Yes it does, if you knew how to spell. S-N-O..."

I was interrupted by the kitchen door opening and Dumbledore sweeping in. Black quickly composed his face into an appearance of bland unconcern.

Too late, Black; he saw your ugly sneer. Not for nothing am I a master of goading people into an incoherent rage.

Dumbledore glanced at each of us in greeting, but avoided my gaze for some reason. He nodded briefly at Tonks, who abruptly stood, catching her chair just before it went over, and left the kitchen without another word.

Dumbledore poured himself a cup of tea and sat in the chair vacated by Tonks.

"Gentlemen," he began, sipping his tea before grimacing and adding a generous spoonful of sugar. "You are both under a considerable amount of stress. If I were able to give you holidays, I would send you both far away from this place, and each other. But there is no rest for any of us these days. I have to be able to trust you both, and not rely upon students to prevent you from hexing each other. Sirius!" His voice sharpened as he spoke Black's name. I was careful not to smirk.

"You know," Dumbledore continued, "that Severus is a very dangerous man."

"So am I," Black protested.

Now I was really struggling not to smirk.

"Of that there is no doubt," said Dumbledore evenly. "But you know the nature of his role in the Order and the abilities he has that make that role possible. Severus is more dangerous than you are. You must avoid provoking him at all costs."

Black flushed and stared at the floor, unseated by Dumbledore's bluntness. I can easily keep my face free of all expression, of course, but I was staggered. I am accustomed to every sort of insult, but praise comes my way all too infrequently, and coming from the most powerful wizard in the world, it almost brought me to my knees. What a truly great man. A man who has been like a father to me.

I should have known it was too good to be true. My whole life has been like that.

Dumbledore abruptly turned around, catching me sneering gleefully at Black. Whoops. "And as for YOU!" He rose to his rather considerable height and placed his hands flat on the table, leaning towards me. "This sort of thing was bad enough when you were sixteen, but now that you are old enough to understand the consequences, it is especially disappointing. As a master of Hogwarts school, you are expected to set a proper example, and not engage in dangerous and impulsive behaviour. What if Harry had been harmed? And all because you couldn't put personal feelings aside for a few minutes. Shame on you!" He wasn't yelling, but his voice dropped towards the end, to an emphatic near-whisper. Despite his harsh words, he was regarding me with so much care and concern I could feel myself blushing. Only the headmaster still had the ability to make me feel twelve years old.

I looked at Black, and he had carefully composed his face into a look of humble neutrality, but his eyes revealed all the smugness he was careful to conceal. Damn him. Once again, I get into trouble for defending myself, while Black gets a slap on the wrist, and a Potter comes off looking the hero.

Dumbledore stood up straight to look at us both. He gestured at the door to open it, and Tonks stumbled in. Dumbledore smiled indulgently at her. As if it's funny that the defense of the wizard world rests upon the likes of witches who can barely manage to put one foot in front of the other.

Dumbledore turned his deceptively benevolent gaze towards me. "Coming, Severus?" he inquired mildly. But it was not a request.

I followed him as he Disapparated, and to my surprise, we were in the middle of Hogsmeade instead of at the castle gates outside the anti-Apparation wards.

He turned to me abruptly. "Go get yourself a drink. You need it." And he Disapparated before I could protest.

He stalked into the Hogs Head, throwing off his cloak as he entered. It was the kind of place where everybody ignored you except the barman. In other words, the perfect pub. Just so long as you performed a Cleaning Charm on your glass before your drink was poured.

The barman regarded him with oddly penetrating blue eyes.

"Firewhisky," Snape demanded wearily, and sat on a stool, right elbow propped on the bar, his chin resting on his right hand, his left hand in his lap. Though he was completely covered from neck to wrists to feet, out of force of habit he kept his left arm down.

The barman nodded, lifting the bottle already in his hand. He poured the drink quickly, pausing beforehand just long enough to allow the customer to cast a Cleaning Charm on the glass, before retreating to the other side of the pub.

The door swung open and everybody looked up in mild surprise as an improbably beautiful woman entered. She wore a simple green robe that emphasised the shimmering auburn hair falling nearly to her waist. Her flawless complexion almost seemed to glow in the dim light of the pub.

After briefly glancing around, she walked towards the saturnine man in black robes at the end of the bar.

Ever since the Barty Crouch debacle, Snape checked everyone's eyes to be certain of the identity of the person behind them. He looked into the woman's large turquoise eyes and scowled. "You couldn't have drawn more attention to yourself if you'd walked in on the Dark Lord's arm, Tonks," he hissed.

She smoothed her robe a bit self-consciously and sat on the stool next to him. By way of making conversation, she said, "My cousin can be a complete prat sometimes."

He snorted. "Only sometimes?" He turned to face the bar and sipped his drink, looking forwards rather vacantly at the bottles behind the bar, the way people do when they are drinking alone.

Seated parallel to him, she regarded those same bottles. "You two have a lot in common."

He made a choking noise. "It's none of your business," he said rather hoarsely. "And I don't want to talk about it." He turned to face her. His black eyes raked her from head to foot, his face expressionless, as if she were an interesting specimen that should be pickled, bottled, and stored on a shelf in a dungeon office. "Are you supposed to cheer me up, or something? He knows me better than that. Not that it stops him from trying."

"Would you rather I approached you as an Auror?"

He was silent for a moment, sipping his drink. Then he cast a Confabulating Charm, which mixes up voices and fabricates an entirely different conversation, somehow matching the vocal sounds with the lip movements of the conversants. In this case, anyone trying to listen would hear a conversation about Quidditch. Incongruous, but less likely to arouse suspicion than silence.

He finished his drink in a swallow, not bothering to grimace. "Frankly, yes, I'd rather you approached me as an Auror. The more I am perceived as mistrusted by the ministry, the more credibility I have in...other quarters." He paused as the barman refilled his glass and turned to regard her critically. "You're a prostitute, then?" he ventured.

"A very high-class one. The sort that only goes with pure-bloods. But still affordable by a Hogwarts professor. And you won't have to justify this meeting to anybody."

He scowled. "If there was nobody meeting me at all, there would be nothing to justify. In fact, it would be preferable if you arrested me. What couldn't wait until the next meeting?"

She smiled brightly, enormous eyes sparkling, leaning forwards as if she were encouraging him to look down her cleavage at the lacy black bustier she had Transfigured from the plain white cotton sports bra she normally wore for work. "Buy me a drink?" she asked.

His face was like stone. Then he said, "If you are as expensive as you say, you can buy your own drinks."

She took a deep breath and reminded herself a little angrily that she was an Auror, and not a firstie who was going to lose lots of points and maybe earn a detention for melting a cauldron in double Potions with the Slytherins. "Tomorrow you must go with me when I buy a Christmas present for Harry Potter."

He didn't react immediately. Then, to her alarm, he actually chuckled. "You don't have the authority to send me anywhere. Or does the headmaster think I have been insufficiently chastised?" He looked pensively at his drink for a moment. "If Potter hadn't stopped me, Black would have learned something. And I wouldn't have hurt him." He smirked slightly. "Not badly. Though he would have bitterly regretted it, the next time he tried turning into a dog."

Trying not to think about what sort of curse her cousin narrowly escaped, Tonks said, "Since the attack on Arthur, Albus has worried about our personal safety, and has assigned partners who have to accompany us whenever we go anywhere, as far as possible. For instance, Kingsley is with Arthur, Molly is with Sirius, and I, well, am with..."

"What is this rubbish?" he snapped, and gulped the rest of his drink.

She reached into her purse and pulled out a mirror, handing it to him. "You use this to tell me if you're going anywhere. We don't have to be side by side. If, say, you have to go to the apothecary in Diagon Alley to pick up supplies, I could be browsing in shop windows nearby. Or I could be in Auror robes, tailing you in a casual but obvious sort of way."

He regarded the mirror in her hand with the sort of derision he might normally reserve for something cute and fluffy. "Fascinating," he spat. "'Worried about our personal safety?' My job is to put myself in harm's way." He looked into the gloom behind the bar and the barman suddenly re-appeared. "Leave the bottle," he snapped at the barman, who complied before disappearing again.

"Just because the headmaster thinks it is a good idea doesn't mean it is." He poured himself another shot and drank it. All that firewhisky doesn't seem to have any effect on him, thought Tonks. Maybe he's used some sort of potion, but then why bother drinking at all if you're going to take something to cancel it out?

He regarded her with those fathomless black eyes. "Your dear uncle Lucius, on top of his usual paranoia, is convinced that you are being used in some covert assignment against the Dark Lord. And then you'll be seen following me all over? Or I'll be observed with all these ... singular-looking witches nobody has ever remembered seeing before? I don't think so." He drained his glass again, and refilled it with a remorselessly steady hand. "If you die on my account, it will mean a lot of tedious paperwork, and Albus will likely assign someone in your place who is even worse than you."

"Albus cares about your safety, even if you don't," she said, wondering where that had come from.

The firewhisky finally seemed to be working. He stood carefully, steadying himself against the bar. His gaze did not waver, but she thought she saw something else in his eyes for a moment. "The sooner you get out of my presence, the safer you will be." He tossed a handful of coins on the bar, took out his wand and was gone before she could protest with the usual cautions against drinking and Disapparating.

Next day, Tonks was firecalled to 12 Grimmauld Place. She tiptoed through the front door and was quietly and carefully hanging up her cloak when the door slammed behind her. Startled, she stumbled against the troll leg umbrella stand, and once again it fell with a wood-splintering crash. Once again, she wondered despairingly why wizards would need umbrellas, or stands to put them in, when water-repelling charms were simple for just about everybody and more effective than umbrellas.

The curtain flew open in front of Mrs Black's portrait, who rolled her eyes towards Tonks.

"Half-breed filth!" she screeched.

"Oh, bugger," muttered Tonks.

Snape stepped beside her, sneering a little wearily at the portrait. "Do shut the fuck up, you tediously hideous hag," he said lazily, and grabbed the curtains to close them.

Mrs Black rolled her wild-eyed gaze towards him. "Foul-mouthed traitor! Murderer!" she yelled.

"Murderer?" he echoed, letting go of the curtains. "That's rich, coming from you!" Eyes narrowing, he took out his wand.

"Penniless groveler! Too bad your father drank the family fortune. Your blood's as good as Malfoy's, but instead you have to lick his boots!" She cackled wildly.

His eyes blazed. "Why you dried-up old ..." he was raising his wand when someone yelled, "SEVERUS!"

Dumbledore strode down the hallway and closed the curtains with a casual flick of his wand. Turning to Snape, he said, "Any one of us would have done what you were about to do months ago, if the Permanent Sticking Charm behind that portrait wasn't inextricably linked to the concealing wards about this house. Come, have some tea." He gestured to the door into the kitchen.

As they followed Dumbledore into the kitchen, Snape turned to Tonks and whispered, "You will not repeat what you saw to anybody."

"Of course not, Severus," she whispered in reply. But he had already turned his back to her and was striding aggressively into the kitchen.

Dumbledore bade them to sit and poured them cups of tea. "Sirius is feeding the hippogriff, and will otherwise stay upstairs while we are here."

Snape nodded impatiently, hiding his relief at not having to confront Sirius. "If I might speak, Headmaster..."

Dumbledore held up his hand. "Severus, I knew you would have considerable resistance to my idea, and I wasn't sure if it would be prudent to include you in the new partnership system. Like you told Miss Tonks, your unique role presents us with challenges. Nonetheless, I have decided to include you because you are no less deserving of protection than any other Order member."

"I beg your pardon? Surely forcing me to stay in contact with someone in the Order will only present me with one more connection to conceal, and one more opportunity for exposure. For instance, what if she tries to contact me when I am in the presence of the Dark Lord?"

Dumbledore replied smoothly, "The mirror is your only method of contacting your partner outside the usual ways of communication. If you are summoned, simply don't take the mirror with you. If you are caught by surprise, contrive to smash it."

Snape glanced briefly at Tonks. "Smashing things is rather more in character for some people." He looked back to Dumbledore and folded his arms, looking somewhat petulant. "I still don't see how it keeps me safer, giving me one more thing to remember."

Dumbledore smiled at the younger man glowering at him. "Ah, but that's because I haven't yet explained how it works. These partnerships are more than just an agreement between two people. It is magically binding. It's a variant on the Fidelius Charm, in which your partner acts as your Secret Keeper."

Snape continued to scowl, but sat back in his chair, tracing his lips with a finger while he thought. "So ... are you saying that you have figured out a way to make human beings ... Unplottable?"

Tonks said, "You can only be tracked by your partner. Who will also be alerted if you are in mortal peril."

Snape sat silently for a moment, then his mouth fell open in astonishment. "If I am discovered ..."

She replied, "If you are discovered, I will know immediately, and will alert the Order. And we will all know where you are, through me."

But Snape was shaking his head. "You can't be risking yourselves on my account before Potter is ready. It will only result in pointless deaths."

Tonks protested, "Who says you will be discovered before Harry is ready? Or that you'll be discovered at all?"

He was no longer scowling, but looked at her expressionlessly, his black eyes even more inscrutable. Then he addressed Dumbledore. "What happens when the term starts? Is she to follow me around at Hogwarts?"

"She will come to Hogwarts sometimes, under the guise of investigating you." Dumbledore regarded him silently for a moment before continuing. "Severus, as you know, I have been unable, after all these years, to get your file at the ministry closed. Well, now we can use that to our advantage. Moody and Shacklebolt are making sure that Tonks gets 'assigned' to your case."

Snape said thoughtfully, "Yes, well, I don't have the gold that some people have to buy the minister's trust."

Dumbledore said gently, "And if the attack on Arthur has taught us anything, it's that we can't have Harry thinking he needs to maintain his link with Voldemort in order to ensure our safety."

Wincing at hearing "Voldemort," Snape replied, "Somehow I don't think Potter is overly concerned with my safety. And besides, surely you're not going to tell him about this new arrangement. Are you?"

"I will tell him that we are taking extra precautions. And you will explain to him in the Occlumency lessons how important it is to sever that link, using the reason we discussed."

But now Snape was smirking. "When Potter is ready to face the Dark Lord, I shall reveal myself as a traitor at the next Summons, thus placing myself in mortal peril. Through Tonks, all of you will easily be able to find the Dark Lord, and bring Potter along for the final battle. Well done, Albus. It's a plan worthy of a Slytherin."

Tonks looked horrified, but Dumbledore only looked sad. "I suspected you would think of that. Let's hope such a strategy never needs to be used."

"Surely you wouldn't do something like that, Severus!" Tonks exclaimed.

"It's unlikely, because I don't believe Potter will ever be ready to face the Dark Lord," he replied smoothly. She looked back at him skeptically.

Snape looked from Tonks to Dumbledore. "I agree to this arrangement," he said smoothly, and took a sip of tea, grimacing at its bland sweetness.

Dumbledore looked older and more tired than usual. "I can't stop you from reaching your own conclusions."

Tonks said, with false brightness. "So are we going to Diagon Alley now?"

Snape sneered. "To buy a Christmas present for Potter? Must I accompany you?"

Dumbledore spread his hands apart. "The charm is strengthened, the more time you spend in the presence of your partner."

Tonks said, "For today, I thought I'd go as myself. And you could look annoyed and angry, like you're being forced to have an Auror escort. Can you do that, Severus?"

He regarded her sardonically. "Let's get this over with, shall we?" he sighed, rising from his chair.

They Apparated to Diagon Alley. Snape assumed his usual soundless, rapid stride, forcing Tonks into a half-run to keep up.

"Will you slow down?" Tonks gasped. "I feel like I'm following you to the dungeons for detention."

He raised an eyebrow at her, but said nothing, and slowed his pace marginally. And then he suddenly stopped and turned. Tonks almost ran into his side.

"If you can't find anything suitable here, you will have to get him something at the apothecary shop, where we're going next before I return to Hogwarts." And he swept into the shop without looking to see if Tonks followed.

She looked up at the sign over the shop's doorway. "Not a bad idea, actually." And she entered Flourish and Blotts.

Tonks had found one of the last hardback copies of Imagining the Animagi, a popular novel for young wizards that Ron had assured her Harry wanted, and went to find Snape, who was browsing through the magazines in the Potions section.

He looked up from the latest issue of "Subtle Poisons and Their Antidotes Quarterly." Smirking, he said, "I found the perfect book for Potter," and handed her a copy of Remedial Potions: Help for the Hapless.

"Thanks Severus. I already found something," she said in a neutral tone in case he wasn't joking. His sense of humour was unpredictable at best.

"Right. The headmaster has asked me to pick up some replacements for the Restricted section. A surprising number of books from that section seem to get lost or damaged, considering they are, well, restricted."

"Do they still have that Screaming Charm on the books if an unauthorized student tries to read one?" Tonks reminisced.

He made a noise that sounded like an affirmative, and said, "I would put a more creative hex on those books. Something more memorable, and therefore, more corrective, but the headmaster continues to brush aside my best ideas."

Tonks grinned. "Probably he thinks your classes are enough of a strain on the hospital wing as it is."

He had his back to her, selecting a book off the shelf. He replied mildly, "The headmaster and most of the other teachers refuse to acknowledge that some students need something more ... compelling to discourage them from inappropriate behaviour." He turned abruptly to look pointedly at her.

Tonks' grin turned a little sheepish. "I still wonder how you knew it was me, even before the real Filch came round that corner."

"Other than your signature trail of destruction?" he smirked. "Filch isn't usually afraid of his own cat."

While they were talking, they moved slowly amongst the stacks of books. He had selected several, and they made their way to the front to pay.

"Damn!" Tonks muttered, looking into her purse. Snape looked askance at her.

"I stepped on my handbag earlier, breaking a mirror. No, not that mirror. I didn't have time to find all the pieces for a Reparo, so I just switched handbags, and I forgot to transfer my money over. Severus--would you mind? I'll pay you back later."

He glared at her in astonishment. "You want ME to ... PAY ... for POTTER'S Christmas present?" he sputtered. "It'll be a cold day in..."

"Otherwise, we'll have to come back later."

"No. YOU can come back later."

"No. Albus insists. We have to be with our partners when we are out in public."

"I don't have time for this," he hissed. He reached into a pocket of his robes and brought out a handful of coins, throwing them down angrily, sending some of them flying off the counter, forcing the clerk to scramble after them as they went rolling about on the floor.

"Thanks, Severus. I won't tell anybody."

Package of books tucked under his arm, he was already striding out the door. Children and adults alike scattered from his path as he swept down Diagon Alley, a fury in swirling black robes and menacing scowl.