Harry Potter was up to his armpits in a cauldron, leaning deeply in so as to clean the very bottom of the vast brewer, when a lively knock sounded upon the thick door of the Potions classroom. The knock hardly presaged another student’s arrival for detention, Harry decided. First of all, it was far too late at night. He himself had been scrubbing cauldrons for over three hours already. Second, a student’s knock would have reflected deference or, at the very least, a certain degree of trepidation. Partway through his Fourth Year at Hogwarts, Harry had become an expert at knowing how students normally tended to knock on Snape’s door when they arrived to serve detention.

In contrast, this knock sounded—cheerful.

Dumbledore?

After casting a quick Tempus, Snape stood up from his desk and straightened his robes, giving the impression that he knew exactly who had the temerity to rap so lightheartedly on his dungeon door while an early January blizzard howled relentlessly beyond the castle walls.

“Come in.”

In response to the Potion Master’s—invitation? as opposed to his habitual command of “Enter”—the heavy door swung wide, admitting the absolute LAST person Harry would have expected to see crossing Severus Snape’s threshold.

“Good evenin’, Perfessor!” boomed Hagrid’s voice, amplified by the close confines of the classroom walls.

Harry’s scrub brush clattered into the bottom of the cauldron when he saw what Hagrid was carrying proudly in his oversized hands.

Not a bowtruckle or niffler. Not even a blast-ended skrewt.

Hagrid approached Snape with a broad smile, bearing a smallish cake. Or maybe it just appeared small because it was Hagrid who was holding it. A familiar type of cake, Harry realized. Hagrid had brought him one quite like it the first time Harry could remember meeting him. Unevenly iced, dotted with a few flaming candles, it was unmistakably a birthday cake. Equally unmistakably made by Hagrid himself, who presented it ceremoniously to Snape.

“Happy Birthday, Perfessor! Sorry I’m a bit late this year. Th’ blizzard wind kep blowin’ out th’ fire in me oven. But I fin’ly got yer cake baked good ’n’ proper.”

Snape accepted the proffered cake graciously. “Thank you, Hagrid. Your efforts and kind wishes are, as always, appreciated.”

“Many happy r’turns, Perfessor!” Hagrid nearly saluted Snape before he spun around on his large heel to head back toward the corridor door.

“Oh, hallo Harry! Di’nt see yeh there! D’tention again?” Hagrid tsk-tsked, shaking his shaggy head. “Yeh shouldn’ upset Perfessor Snape so of’n. Cauldron scrubbin’s a nasty biz’ness, Harry. Oughta avoid it, if yeh can, eh?”

The Gryffindor ignored the pronounced snort from the vicinity of the cake and gave Hagrid a rueful grin.

“Right!” Harry couldn’t help rolling his eyes as he agreed, given that Snape had his black gaze pinned upon Hagrid and himself.

The half-giant winked back at him.

“Blizzard’s still bad, I take it?” Harry asked, although Hagrid’s appearance spoke for itself. The parts of his thick, unkempt hair, wild beard, and hairy coat that didn’t have an actual layer of snow upon them were saturated heavily with the melt.

“Aye,” Hagrid nodded seriously. “Don’ even THINK ‘bout goin’ out in this mess, Harry. We wouldn’ fin’ yeh ‘til spring—“

“Mr. Potter is in detention, Hagrid,” Snape’s voice sounded a firm dismissal. “He can catch up on his social life and the most recent weather report at a later date.”

“Right, Perfessor. G’night, and happy birthday again. G’night, Harry.”

The door closed gently behind Hagrid.

Harry leaned way down into the cauldron to retrieve his scrub brush, then straightened to look at Snape, who had placed the cake upon his desk. The candles still burned merrily, but the wax didn’t seem to be melting as it would have with Muggle candles.

Once he had reseated himself behind his desk, the Potions Master’s gaze seemed transfixed by the tiny flames, as if he were staring beyond them at something which Harry himself could not see.

After several long moments of silence, during which the birthday candles flickered spasmodically whenever a blast of blizzard wind found its way through the cracks in the ancient stone walls, Harry ventured a comment.

“Hagrid brought me my first-ever birthday cake. Well, the first birthday cake I could remember. That was the first time we met. My eleventh birthday, just before I came to Hogwarts.”

Snape didn’t comment, nor did he look away from the candles. At least he hadn’t cast a Silencio on Harry, so the teen continued, “I couldn’t believe he’d baked me a cake and decorated it. I was a complete stranger to him. Or at least he was to me. I’d never had a birthday before. Well, yeah, I’d had BIRTHDAYS, but no cakes. My relatives never celebrated my birthday.” He paused, reflecting. “Actually, I never got to eat any of Hagrid’s cake. He was too busy telling me I was a wizard, which explained why those weird things had been happening. I didn’t even know magic was real back then.”

Snape was still staring at his birthday candles. Harry couldn’t tell whether the man had heard a single word he’d said.

“So Dudley ended up eating my birthday cake all by himself, even though he’d had his own birthday with a huge cake and tons of presents just one month earlier.”

Snape’s brow furrowed slightly.

“And then, after he ate all of my cake, Dudley sprouted a pig’s tail.”

THAT got Snape’s attention.

“A PIG’s tail?”

“Yep. With a curlicue and all.” Harry laughed. “Boy, did he panic!”

Snape was staring at him along the full length of the classroom. “And this happened after he ate all of your birthday cake?”

Harry nodded, tapping the scrub brush against his reddened knuckles. “But that was okay, because Hagrid took me to Diagon Alley, and it was the best birthday ever, finding out I was a wizard. Hagrid gave me my owl, Hedwig, as my first-ever birthday present.” Harry smiled in remembrance. “Hagrid was my first-ever friend.”

Snape considered him thoughtfully over the birthday candle flames. “A PIG’s tail.”

Harry nodded.

“MORE accidental magic, Potter?”

Harry’s eyes widened. “Er…”

Snape stared at him.

“Well… I certainly wouldn’t have done it on purpose,” Harry temporized, remembering vividly how Hagrid had aimed his pink umbrella at Dudley’s broad backside. “In spite of the cake.”

Snape continued to stare into Harry’s eyes for another moment, then smirked slightly. “I see.”

Harry waited, but Snape made no further comment. The boy shrugged, then leaned down into the huge cauldron again, standing on tiptoe to reach all the way to the bottom. The copper rim dug into his midsection. He cautiously eased a few inches further forward, extending the sudsy brush as far as his aim would reach…

“Potter!”

Harry nearly toppled entirely into the cauldron. His trainers flailed in midair as he tried to regain his footing. He was still struggling to get his belt buckle to lift back up over the rim when Snape plucked him from his undignified dangling position and set him upright on his feet with an impatient huff. Harry swiped his hand through his hair, trying to rid the strands of soapy residue.

“Thanks, Professor,” Harry mumbled, his red face staring down at the floor.

“Come,” the Potions Master ordered, his robes already billowing away toward his desk. He Accioed a stiff wooden chair and placed it directly across the desk from his own leather-bound chair. “Sit, Potter.”

Puzzled, Harry sat, staring at the birthday candles’ cheerfully-flickering flames.

“Due to circumstances which I do not intend to discuss with you,” Snape sneered as he settled his endless ebony robes into his own seat,” my family also … refrained … from celebrating birthdays.”

Harry’s eyebrows shot up toward his fringe.

“That being the case,” Snape continued, “I did not actually have a birthday cake myself until after I came to Hogwarts.”

“Oh.” Harry couldn’t even think of a more adequate response.

“My best friend in my class at Hogwarts—someone from my hometown, in fact, who was aware of my personal situation—happened to mention it to Hagrid during our First Year at school.”

Harry had to wonder what kind of “friend” would go around gossiping personal, private, and possibly embarrassing information to Hagrid, of all people. Hagrid, who—despite his heart of gold—could never manage to keep a secret SECRET.

“On my birthday that year, I received an unexpected invitation to visit Hagrid’s hut for tea. A birthday tea, as it turned out, complete with my best friend and a cake baked from Hagrid’s father’s favorite recipe, handed down from Hagrid’s human great-grandmother.”

Harry’s mouth gaped. “Hagrid fixed you a birthday cake? He threw you a party?”

Snape nodded. “My very first. The party itself was quite modest, with just the three of us, but Hagrid has continued to bake me a birthday cake every year since then. Even during the years after I graduated, before I returned here to teach.”

“Wow!” Harry smiled at the little cake appreciatively. The lavender icing spelled out “HAPPEE BIRTHDAY P. SN”, completed in brilliant fuchsia icing: “APE”. Hagrid must have run short of blue coloring.

“Hagrid is a terrific friend, sir!”

Snape silently nodded agreement, then asked, “Has he baked other birthday cakes for you, Potter?”

Harry laughed. “Oh, no. Just the one that Dudley ate. Mrs. Weasley has been owling me birthday cakes, though, so I finally do get to have a private celebration every summer at midnight on my birthday in my bedroom at the Dursleys. And Ron and Hermione send gifts.”

Snape contemplated the candles, then waved his wand, extinguishing all other illumination in the Potions dungeon. His pale face glowed warmly in the light from his cake. The older wizard looked speculatively at Harry and smirked.

The-Boy-Who-Lived felt his stomach contract uneasily. Something odd was about to happen, he was sure of it…

“You may sing to me.”

“WHAT!”

Harry gawked at the man. Surely Snape hadn’t just imperiously ordered him to SING?!

“The birthday song,” Snape clarified. “No more, no less.”

“Oh…” Harry’s mind floundered, trying to right itself. “I—mm—well, I really don’t have much of a voice, sir. To sing with, I mean.”

“I’m certain even YOU can manage to sing ‘Happy Birthday’, Potter.” A … long … pause... Then, “I’m not getting any younger here, Potter…”

“Er—right. Okay. Here goes…” Harry cleared his throat and surrendered himself to the surreal, singing:

“Happy Birthday to you, Happy Birthday to you, Happy Birthday [oh, CRAP, did he REALLY have to call him 'dear'??!] dear [Harry nearly choked on horrified silent laughter] Professor Snape, Happy Birthday to you.” [OVER! Thank MERLIN, it was OVER!!!]

Without preamble, Snape abruptly leaned forward and blew out the birthday candles, plunging the Potions dungeon into utter blackness.

Harry couldn’t help wondering what Snape might have wished for before blowing out the candles. He knew better than to ever ask. A tendril of blizzard wind squealed between two stones, chilling Harry’s exposed, damp arms. He wished Snape would hurry and relight the classroom lanterns and candles. It was … unnerving … sitting here in the total darkness with the unpredictable man, after all.

“Thank you, Potter.”

Harry was shocked into speechlessness for a moment, then he replied into the black void, “You’re welcome, sir. Happy birthday.”

A rustle of fabric from Snape’s robes preceded the quick wave of his wand, and the classroom lit up again.

Snape deftly flicked his wand at the birthday candles, Vanishing them, and conjured two plates, two forks, and knife with which to cut and serve the cake.

“Um … you’re actually going to eat Hagrid’s baking, sir?”

Snape just looked at him. “Did your cousin, Dudley, come to any harm? Besides the tail?”

“Well, no,” Harry realized. “He actually seemed to enjoy my birthday cake. It’s just that Hagrid’s rock cakes tend to…”

Snape was still looking at him. “Did I not say that the recipe came from Hagrid’s paternal HUMAN great-grandmother?”

“Yes, sir.”

“Well, then.” Snape served up a generous slice for each of them.

Harry wiped his slightly soapy hands dry on his trousers and, following Snape’s lead, picked up his fork and began to eat. A few minutes later, as he swallowed the final tasty morsel, he decided that Hagrid’s rock cake recipe must have come from his mother’s giant side of the family. He never saw the wand…

“OBLIVIATE!”