Severus Snape was not a happy camper.
Not that he was ordinarily filled with sweetness and light; he rather felt that any milk of human kindness he may have once possessed had curdled long since. Still, he was in an extraordinarily foul mood, what with his planned trip to the Pan-European Potions Symposium being cancelled at the last nano-second, and then Dumbledore cheerily inviting him to fill his time with long-overdue paperwork that Snape had rather hoped had been forgotten about.
Indulging his towering rage, or at least his monumental snit, he threw open the door to his classroom and then really wished he hadn't. For upon entering he was confronted with the image of Potter's sycophant Weasley and that damnable Granger girl, in far less clothes than he would have ever wished to see any student, let alone those two.
The sound of the door banging had evidently pulled them from their own, and they stared at him with a horror that he returned a hundred-fold. "Don't just lie there, you ninnies, put your clothes on!" he thundered, averting his eyes as they scrambled to obey.
As soon as they had moved away from the desk, he walked around to his chair, needing the security of his professorial position. He was about to pull himself close to it in order to rest his arms on it in his preferred pose for lecturing the guilty, when he remembered what had just been happening on its surface and decided rather hastily to remain with his hands firmly on the chair's arm rests. After a moment of staring at the top of Granger's amazingly horrible hair and Weasley's purple-red face, he managed to say, "Explain."
There was a strangled noise from Granger, something between a squeak and a sob, and Weasley turned an extremely ghastly shade of white, even his numerous freckles (and Snape felt he would have lived a much happier life without knowing exactly how far those freckles extended) seeming bleached by his terror. After several moments in which Snape glared just as fiercely as he knew how, the boy finally managed to croak out, "We--"
"Tell me, Mister Weasley, of all of the places in this castle to be caught in delicto much too flagrante for words," he paused to look down his nose at Granger, who appeared to be attempting to shrink in on herself to the point of implosion. "Why, in the name of heaven and earth, would it be MY desk that you choose to violate?"
Several long moments went by before a small voice that he would never have believed could come from the same Granger that swanned around the castle telling everyone and everything how to run their lives said, "Tradition."
"I beg your pardon," he said in a voice that had less resemblance to begging pardon and more to condemning to the gallows.
The Weasley spoke up then, as his lady fair seemed to be speechless for once in her know-it-all life. "It's tradition... Sir."
Snape glared at the orange haired twit. "Mister Weasley, I have been at Hogwarts for a very long time, and I have never heard..." He trailed off for a moment, trying to think of a way to phrase the remainder of the sentence without shouting or, Merlin forbid, blushing.
Weasley flinched, then swallowed so hard that his abnormally protuberant Adam's apple moved visibly. After taking a deep breath, the boy said in a rush, "Um, I think it might have started when Bill was here."
"I see," said Snape, feeling in his bones that he was going to regret his next words. "And what, precisely, does this tradition consist of?"
Showing his amazing range of possible skin coloration once again, the Weasley boy turned a sickly green. "Er, of, um, doing.... That. Before graduation. And then carving a notch in to show it'd been done."
Snape couldn't prevent himself from looking at his desk in horror. He'd thought all the various damage to his desk was done by carelessness and Peeves, and simply wrote it off as normal wear and tear. "Every Weasley?"
The boy nodded, then said, "Although it's not just us, it's everybody now."
"Do you mean to tell me," Snape said in a whisper that was rising in volume and intensity. "That MY desk is, is, is being profaned by every dunderhead that happens to talk a girl out of her knickers?"
The boy flinched in the face of his thundering, but Granger's head shot up. With the insufferable tone that always made him dread calling on her in class, she said, "Women are allowed to enjoy--"
"Don't finish that sentence, Miss Granger," said Snape, standing up and slamming his fist down onto his desk. He would have continued, adding a threat, but the desk, which he had been after Dumbledore to replace for the entire school year, chose that particular moment to finally give up the ghost. The top splintered into a spider's web of cracks radiating from where he had hit, then the entire desk shuddered and wobbled and simply fell apart.
While that had been unexpected, the real shock was when first one, then another voice yelled and cursed from under the remains of the desk. After a moment, the flying sawdust cleared enough to show two extremely unlikely people crawling out from under the rubble.
"Ginny?" was gasped out by Weasley, at the same time that the girl in question reached up to wipe a trickle of blood from Draco Malfoy's temple. "Ginny, what are you doing here?"
Malfoy smirked in a way that made Snape hasten to say, "I would prefer not to hear the details, if you please." Draco nodded and pulled the girl back to his side when she blushed and would have stepped away.
"Y- you can't. Not with him!" Ron Weasley's voice was pathetic and pleading as he whined, "What about Harry?"
The girl, whom Snape had never particularly taken notice of besides a general interest directly after the Chamber of Secrets incident, rolled her eyes and said, "What about Harry? It's because of him bringing Luna here that I found out about this at all, you know."
Snape felt his stomach churn at the thought of having eaten his lunch on the same surface that had once held a naked Harry Potter. The Weasleys were screaming at each other now, with Granger making occasional comments trying to make both sides see sense, or at least her definition of it, and Malfoy making faces from behind his girlfriend's back.
Finally, he could handle no more. "ENOUGH!"
The four teenagers fell silent, all but Draco looking at him with white-knuckled terror. "The only reason I am not having you all expelled is because then I would have to explain the reason why, and I fully intend to wipe this memory from my mind at the earliest opportunity, in an effort to prevent permanent psychic scars."
Draco looked like he was bursting to say something, but apparently there was something in the way that Snape's gaze whipped around to him that convinced him of the necessity for silence. Closing his eyes in an effort to regain control, Snape said quietly, "Just... Get out."
Seconds later, the door slammed behind them and Snape sat down heavily and buried his face in his hands. First thing in the morning, he would have a new desk brought in. For now, his priority was finding a way to seal his classroom from intrusion after hours and then finding how much oblivion a bottle of scotch could provide.