Rather predictably, the Owlery did not provide any answers: as Snape's incongruously dainty Patronus informed Harry, the attacker must have clued in and vanished the remainder of the powder from themselves halfway down the stairs. On a whim, Harry reached to pet the silvery doe. It regarded him with big distrustful eyes for a moment before vanishing into thin air. Once again, Harry wondered if he was a fool to be interested in a man whose dislike of all things Potter had started a decade before Harry was even born.

His thoughts soured even more as they turned to the murderer. They were no closer to finding who poisoned Smith than they had been before. Nobody showed him open antipathy so far, but then again, the murder wouldn't risk it, right? Harry resolved to pay closer attention at the dinner. Who knew, maybe the tension and wine would loosen some tongues.

At dinner time, Flitwick brought the flying chair. Surprised by Grubbly in the doorway of the Hospital Wing, he dropped it at once and hit the man with an Incarcerous, McGonagall's warning not to attack coming a second too late. His cheerful disposition made it easy to forget that the diminutive Charms Professor was once a duelling champion.

"Is anyone else going to tie me up today? What's one more," Grubbly muttered, and McGonagall looked at him speculatively.

Judith watched the altercation with wide eyes, obviously surprised at this side of her teachers. It took some effort to convince her to use the chair instead of stubbornly trying to get up, but soon Harry was walking behind her into the Christmas dinner. She seemed to be the only one eager for it, having shyly asked to bring a dress robe from the dormitories that Babbling had helped to get her into over her hospital gown.

Harry himself would much prefer to have a private celebration with Snape than another installment of tense sniping, and was momentarily lost in a daydream as to what such celebration might entail on the short way to the staffroom.

"Judy!" David ran to his sister only to stop at the sight of Grubbly supporting McGonagall. If Judith was obstinate about the chair, she had nothing on the Headmistress, who had rejected all Harry's attempts at reason outright, insisting that the absence of the captain was detrimental to the morale of the crew. She had never missed a Christmas dinner all her years of working in the school, she said, and was not going to start now.

It was obvious from everybody's curious but not at all surprised expressions that Babbling had gone ahead and shared the news. Harry was both relieved and peeved; this saved them a commotion his patients certainly did not need, but at the same time, he missed the reactions that could have betrayed the culprit. He silently berated himself for turning his full attention to Snape as soon as the situation with the Headmistress resolved and not asking Babbling to keep her counsel; she was obviously not one to hold on to fresh gossip for long.

The elves outdid themselves with the Christmas dinner with a tender and succulent turkey stuffed with apricots and hazelnuts as the centrepiece of the table, but the atmosphere in the staffroom was far from festive. Flitwick followed Grubbly's every move with his eyes, and Alicia stared at McGonagall with undisguised suspicion. By an unspoken agreement, nobody questioned the pair further, but the unease was palpable in the air. If the stranger in the castle wasn't the murderer, then who was?

Trelawney broke the tense silence. "Remember I saw a man in your teacup, Wilhelmina?" She had made an effort to dress up for the evening, shedding her numerous shawls and donning a long multicoloured dress with swirling patterns that would not look out of place in a hippie commune.

"Wilhelm," Grubbly corrected through his teeth for the umpteenth time.

Calliope and Emily were watching the exchange curiously, visibly struggling to make sense of either of them.

"You can see what happens just by looking into a cup?" Callie asked, picking at the frills on her formal robes that made her sit straighter and stiller than usual.

Trelawney adjusted her glasses. "Everyone can see that, dear child. But precious few are able to interpret the signals that Fate sends us."

"That's really deep," said Emily. Unlike her friend, she wore a comfortable-looking muggle dress with a cartoon character. Harry was happy the newer generation could express their Muggle interests freely. Dean had got so much flack for loving football even in their relatively open-minded Gryffindor dorms, and for all Hermione had never been anything less than proud of being Muggleborn, she had eschewed any real connection to Muggle culture early on, focusing on the wonders of magic.

Trelawney nodded, and answered Snape's undisguised snort of derision with a brief glare. By now, Harry was used to seeing the two expressing their distaste for each other, but its venomous intensity still surprised him coming from the usually ethereal Divination Professor.

Looking intrigued, Emily asked, "So can you tell who—"

"You own a gerbil, don't you?" Trelawney interrupted her. "Be careful, it may face mortal danger very soon."

Emily patted her oversized pocket with a panicked expression on her face just as Oliver shot a stunner at the bowl of cranberry sauce nearest to him with an unmanly shriek. It spilled onto the tablecloth, and something small scurried across the table.

"Don't hurt him!" Emily shouted when Oliver raised his wand for the second time.

Snape caught the sandy-coloured rodent as it ran past him.

Everybody's eyes turned to him as he lifted the gerbil on his palm. It sniffed around, whiskers twitching, before sitting still and looking up at Snape benignly. If one still needed any further proof that it was not an animagus, there it was. No person, no matter how deeply lost in the animal's mind, would be this serene when faced with the angry Potions Master.

Emily froze on her seat, fearful eyes trained on her pet. "S-sorry!" she stammered. "I just couldn't leave Gilbert all alone in the Tower for Christmas!"

Filch, who was sitting on the other side of Oliver, murmured something about mannerless brats and looked at Snape in an obsequious way, clearly expecting him to berate the girl. Harry—along with everybody at the table, he was sure—braced himself for an explosion.

Which did not follow.

"Keep better track of your pet, Miss Chang," Snape said instead, offering the gerbil back to Emily, who rushed to his side. As soon as Snape put it into her arms, she nestled it close to her chest.

"Thank you, Professor!" she beamed, letting Gilbert disappear into her pocket.

Apparently, Christmas still was a time for miracles. Harry turned to Snape with a grin.

"Wipe that stupid smile off your face." Snape's hiss could decently pass as Parseltongue, making Harry's grin widen even more.

Babbling waved her wand to turn on the radio. After a few minutes of white noise and more wandwork from Flitwick, where he tuned into some Spanish station and what sounded like throat singing in Gobbledegook, the voice of Lee Jordan filled the room.

"Santa will have trouble getting to Hogsmeade and Hogwarts tonight. Scotland is still caught in the worst magical storm since that time Aberforth's experiment with homebrew in Hog's Head went horribly wrong, but if you are there and listening to our Christmas show right now, we have a special surprise for you..."

"With any luck, this is a sign that the storm will abate soon," said Alicia. "I didn't manage to get any reception on the wireless this morning."

"The murderer must be thinking they don't have much time too, attacking Professor McGonagall like that," said Oliver, emphasising his words with a wave of his fork.

"Time for what," Snape asked. "Please share your insights into the psyche of our murderer, Wood."

"Let's leave this to the Aurors and the press," Alicia interjected.

Harry looked around the table, trying to gauge the reactions. Both Oliver and Grubbly winced at Alicia's remark, but that could well be in response to mentioning the press specifically. Nobody else seemed fazed by the topic that had become a staple of their dinner conversations by now. Flitwick seemed more interested in the ham on his plate, and Trelawney was on her second glass of red already, scrutinising it she would her teacup, perhaps to test the 'truth in the wine' theory. It was remarkable how fast even the most extraordinary circumstances became mundane. Only Judith was watching everybody with wide eyes. This must have been a hell of a lot to wake up to.

On the wireless, Ludo Bagman was trying and failing miserably to sing Accio Christmas by Celestina Warbeck, a WWN's number one this week.

"This is horrible." David winced as he hit a high note.

"The poor dear is trying his best," said Babbling, eager to change the subject of conversation. "It's a charity record, after all. He's raising money for a worthy cause."

"The goblins tried to break into the studio while he was recording," Oliver said between mouthfuls of roast potatoes. "The poor sod still owes them gold."

Harry snorted. "At least we know now which worthy cause he's raising money for." He had zero sympathy for Bagman after the man swindled the Weasley twins in his fourth year and made his experience with the Triwizard Tournament so much more exhausting.

"You also sang a Christmas charity song some years ago, didn't you, Oliver?" asked Flitwick.

"Five years, to be precise, but they still put it on occasionally." Oliver puffed his chest and sent a non-too-subtle sideways glance at Alicia.

"The wireless approached me to do the recording once or twice since I became the Headmistress," McGonagall confessed.

"You should have," said Grubbly. "You have a lovely voice."

"The school's need for extra funding would have to be truly dire before I agreed to something like that. Hogwarts has a reputation to uphold."

"Oh, come on, Minerva, live a little!" Babbling said from the other side of the Headmistress, offering her a Christmas cracker. "Remember our Sybil's appearance on the Christmas show last year? Even that, everybody forgot by Valentine's. One little song won't ruin your reputation." She turned to Trelawney, who was looking rather lemony. "No offence, dear."

Harry, who had spent the last Christmas dealing with the nastiest magical stomach flu outbreak in his memory, with hardly a minute to take a piss let alone listen to radio shows, looked over at Snape questioningly.

"They asked her over for some fortune cookie predictions for the next year, but Sybil managed to fail even at that simplest task by showing up drunk as a newt and rambling some nonsense instead," Snape explained under his breath, but not low enough for Trelawney, sitting across the table from Harry, not to hear him.

"Oh, I remember it," Oliver said with a laugh. "Didn't you diagnose black holes in Jordan's chakra that day?

"And he still has them," Trelawney said through her teeth, shifting her glare from Snape to him.

"That was some show." McGonagall pursed her lips briefly before pulling at the other side of the proffered cracker. In a shower of confetti disappearing just before landing on the plates, a golden paper crown popped up, which she handed over to Babbling to go with her robe.

Alicia and Oliver joined in, and Harry was gratified to see a happy look on Judith's face as she and her brother pulled their own cracker. Snape sent Harry a warning glare lest he tried to offer him one, and the glass of wine he had already drunk prompted Harry to answer with a wink and reach for it anyway. Before he could take it, however, Trelawney leapt to her feet, wand out.

"Riddikulus!" she yelped, pointing it at a deck of tarot cards and Christmas-themed woollen socks that popped out of her and Flitwick's cracker. When nothing happened, she looked around sheepishly and sat back down.

Flitwick sighed, pocketing the socks and vanishing the deck, but not before he had moved the more than half empty pitcher of wine further from her reach.

"Please excuse me," Trelawney said in a wobbly voice. "Nerves."

Oliver harrumphed.

"Didn't you just try to shoot that poor rodent?" Grubbly asked him snidely.

Flitwick tried to defuse the situation. "We are all understandably stressed out."

The thin veneer of Christmas cheer evaporated again, and everybody returned to their meal to listen in silence to the upbeat voice of Lee Jordan goofing on the wireless. When a Christmas pudding popped out of nowhere in the centre of the table in its flaming glory, Harry instinctively reached for his wand. It appeared he wasn't spared from the general feeling of paranoia in the room, but to his relief, nobody seemed to notice.

Or maybe somebody did. Under the table, Snape's knee bumped his own and lingered, touching him a moment longer than necessary. For a second, Harry forgot how to breathe. Was it an accident? No, he knew very well that nothing was ever accidental with this man. The gesture certainly managed to settle Harry's nerves, but if Snape simply wanted to calm him down, it was a surprisingly new development where before he would have opted for a mocking comment instead. Not one to second-guess for long, Harry experimentally nudged Snape's foot with his own in thanks.

Their silent back and forth certainly made the rest of the dinner more bearable, giving Harry strength to sit through Alicia's speech as she raised her glass in memory of Smith. The students were talking between themselves in an undertone, and when Gilbert the gerbil made his appearance for the second time in Emily's hands, McGonagall raised unsteadily from the table.

"Don't end the evening just yet on my account," she said. "I hope you won't be keeping me overnight in the Hospital Wing, Harry?"

Harry would indeed prefer to do that, but it was Christmas, after all. "No, but I'll need to check up on you in the morning, Headmistress. Get me if you feel worse, though."

Despite McGonagall's words, as soon as she left, leaning on Grubbly, everybody rushed to finish the meal. Both Flitwick and Babbling volunteered to accompany Alicia and the girls, claiming strength in numbers, and doubled down on that after Oliver's vehement protests that he could protect them well enough himself. Alicia took deep fortifying breaths. Her expression reminded Harry of the seconds before she took a Beaters Bat from George and chased Oliver around the pitch sending Bludgers at him in Harry's second year. Only the presence of her students and colleagues seemed to keep her from snapping this time.

"Are you in need of a companion to walk you up your tower as well, Sybil?" Snape asked Trelawney with a mocking bow. "It is rather far from here, after all, and who knows what horrors you might divine in the shadows. The school cannot risk our prophetess to lose her mind to another sock waiting in a random corner of the castle."

She sent him a look full of loathing and rose from the table. "I'd hate to ask a dungeon dweller like you to leave his realm, considering what happened the last time you found yourself in a tower. The school cannot risk our current Headmistress as well." She turned on her heels and headed towards the door with a slightly unsteady gait, bracelets clinking on her arms as she wrenched the door-handle.

"Must you always bait her, Severus?" Flitwick asked under his breath.

Snape met his question with a defiant silence. Sighing reproachfully, Flitwick turned to herd the first-years out.

"The school is not what it used to be, I tell you," Filch grumbled under his breath. He wiped his forehead with a crumpled handkerchief, leaning heavily on his cane. "With the old Headmaster, we would gather around the fireplace to burn the Yule log at this time. What do these young people know about honouring the tradition?"

Alicia, who happened to be passing him, made a face. "The atmosphere is heated enough already."

"Happy Christmas, everybody," Babbling said, adjusting her robe on her shoulders. "Don't waste the rest of the night on petty squabbles."

David asked to spend the Christmas Eve with his sister in the Hospital Wing, and for a moment Harry expected Snape to refuse, still riled up, but he gave the boy a curt nod.

"Well, this was fun," Harry said to Snape under his breath.

"At least it was mercifully short, which is more than could be said about our usual staff parties."

"Last year I spent my Christmas Eve and Boxing Day dealing with the slug-vomiting outbreak, so this seems like a step up." He cursed his tongue. Had he really just brought up vomiting slugs to the man he had been flirting with for the past two days? No wonder he was single.

"Boxing Day is yet to come. I'd be loath to encroach on Sybil's bread and butter, but I predict the next move from our perpetrator, together with more bothersome stupidity from the students, who tend to seek trouble even more than usual this time of the year."

"Admit it, that gerbil melted your heart."

"I did consider confiscating the rodent to test some experimental potions," Snape said with a put-upon expression. "And if you insist on bringing it up, I still might."

Harry smiled and looked across the staff room, only now noticing that everybody had already left. Only David stood rocking from heel to toe next to Judith in her chair, waiting for Harry in the doorway. The wireless still hummed softly, and the spilled crackers covered the table that was left laden with delicious food. The night still felt young.

"It's too early," he said, emboldened. "You should come for a Christmas nightcap."

"It's a tempting offer, but we wouldn't want to give the students fuel for any unfounded rumours, would we?" Snape pointedly looked at David who was throwing curious glances at them.

Harry sighed. The answer was expected, but at least it was worth a try.

"There's Avicenna's biography in Poppy's office," Snape said after a moment of thought. "It might help you pass the time. Many colourful pictures. Goodnight, Potter."

With that odd and vaguely insulting advice, Snape strode out of the room.

The elves had already brought David's things over and lit the fairy lights on Judith's bedside table by the time Harry and the students got to the Hospital Wing. The fireplace crackled merrily, adding a cosy feeling to the spacious ward. It was almost easy forget about the farthest corner where Smith's body was lying behind the screen. David gave it a brief nervous look the moment he stepped inside, only to studiously avoid it and focus his attention on his sister from then on.

With warnings not to stay up too late in what he hoped to be a suitably stern tone, Harry ran diagnostic charms over Judith and left them to their own devices. The matron's office was not a particularly inviting place to spend the rest of the evening. The elves had not bothered to light the fire here and Harry could almost see the puffs of his breath, but he didn't fancy going to bed just yet. Curiosity winning over him, he found a green tome with worn away, once gilded letters on the shelf.

As soon as he took the book out, the shelf slid forward and away to reveal a niche, causing Harry jump in surprise. Instead of a stone wall, there was a wooden partition. Cautiously, he knocked.

The partition slid with a much heavier sound than his own shelf, revealing Severus Snape in the middle of his own office.

"Neat." Harry peered inside before stepping aside and letting Snape in with what must have been one of his silliest smiles.

"Indeed," Snape said as the shelf on his side readjusted behind him. His hair was tied at his nape, emphasising the severe geometry of his face, and he was wearing the deep green, almost black dress robe he had had on for the Christmas dinner. It suited him, but Harry wondered if he'd ever get to see him in less formal attire.

"Do you use the passage a lot?" Harry asked.

"It's convenient if the Hospital Wing has a critical patient. The Floo system is rather unreliable, as you can see."

Having checked that the Shaws were safely in their beds, engaged in hushed whispering with the lights out, Harry led Snape to Madam Pomfrey's living room. The candles sprung to life when they crossed the threshold, to fill it with a warm but muted light. It still felt like an intrusion, being in this old-fashioned, feminine space full of doilies and strange memories, but it was better than trying to have any kind of moment in the office. After this dinner, he was confident their previous interactions were building to something that did not exist solely in his head, and was eager to explore it, even if the circumstances were far from ideal.

He had not expected to feel this connection so strongly just after three days, but when had any emotions between them been anything but strong? Whatever this was they were starting, it could never be casual. Was it worth pursuing a relationship after the school resumed and he would be back to his own demanding workload? With a man who might well face Azkaban charges in the near future, no less?

Catching Snape's dark eyes and holding his gaze for a moment, Harry knew the answer to this question. It could be the start of something meaningful, if they managed to not kill each other first, of course.

He moved to get the rum he confiscated from David the other night, hoping against hope that it was at least drinkable, but Snape stopped him, sitting down on the paisley sofa and producing a bottle of Scottish whiskey with a golden stag on the label.

"Minerva's early Christmas present, doubling as an apology," he explained, conjuring two short stocky glasses on the coffee table. "I'm still not sure about the exact message here, but it will certainly taste better than whatever you got there from Mr. Shaw."

Harry sat beside him at a distance just this side of proper, half-expecting Snape to hex him for his audacity, despite all the signals. He eyed the year on the label. "The only thing I consistently get from my own boss for Christmas is budget cuts for my ward," he said. Then again, Hogwarts had a fraction of the staff of St. Mungo's, who lived in close proximity for years and decades. For better or worse, they felt like a family, however dysfunctional.

"Albus used to send all teachers socks for Christmas," Snape said with a distant, slightly melancholy look on his face, pouring the golden liquid. "Minerva always said that we were not house-elves, even if our workload suggested otherwise, and if that was his way of dismissing us, he should have spoken clearer."

Harry smiled and raised his glass slightly. "To better understanding."

"To better understanding."

Tasting the burning liquor with its faint aftertaste of honey and heather, he watched Snape do the same, following the workings of his throat, unbound by the high collar once again. When he drew his gaze away from the sight, he noticed Snape watching him intently. He scooted just a little bit closer on the creaky sofa before a half-formed thought stopped him in his track. "Wait. Socks."

Snape stared at him in irritated incomprehension. "What?"

"Trelawney freaked out at the mere sight of them earlier, remember," Harry said slowly. He recalled McGonagall mentioning a similar scene this morning. Didn't she say something about... "Was this reaction because of Dumbledore?"

"There's no telling what's going on in the sherry-addled workings of Sybil's brain. I doubt she has any ill feelings towards Albus. He's the only reason she has a job, which she should be very grateful to keep."

Harry put his glass on the coffee table, gears whirring in his head. Something was just outside his reach, something that did not sit right. He sprang to his feet to pace the worn Persian carpet, from the fireplace to the window and back. The roaring of the storm outside had dwindled to an occasional howl, muted moonlight breaking through the clouds. "What if she wasn't grateful, what with all the strings attached?"

"What are you implying here?"

"You said you didn't know who else the Headmaster gave those vials with poison to. Why wouldn't he give one to the bearer of the most important piece of knowledge in the war?" Harry looked out of the window, where the blizzard had finally tapered off to lazy snowflakes. "Bugger."

Snape joined him at the wide windowsill with its houseplants in colourful flowerpots, and together they watched a cloaked figure hurrying through the gate, leaving a path of melted snow behind.