Bettina Rookham checked the Great Hall's ceiling for the morning's weather, then wrinkled her forehead. "What are all those pipes?" she asked the table at large.

Severus shrugged, as did everyone else within earshot. If a good Slytherin Pureblood like Rookham didn't know, and none of the others knew or admitted to it, he might as well keep them wondering about both the pipes and him. There was no need to drop a tidbit of apparently-Muggle culture in front of them. He simply wasn't feeling obliging enough to tell her that the shadowed and cobwebbed set of pipes above the Head Table was a neglected church-sized organ. His father had dragged him to Sunday services patiently for years in an attempt to save his son from the evils of ‘black magic.’ There Severus had learned to sing passably well, to identify an approaching storm through stained glass, and to expect an average of 3.2 logical errors per sermon. He felt that nobody currently at table needed to know this, either.

He had wondered before whether the organ had been in regular use at some point, and why it had been installed at all. Now he wondered what he might do with it.

A gaggle of Gryffindors came in to breakfast, Lily in the center as always. Thanks to the Marauders' serenade last year, Severus knew her birthday was exactly a month away. Suddenly he knew exactly what to do with the instrument.

He devoted himself to sausages rather than look as though he were up to something -- too many people tended to jump to conclusions and try to hex him first -- and began to work out details. Music first. Too many birthday songs were vapid and horrible; in fact, all of them were, now that he thought of it. The only thing Lily had ever heard him hum was the Funeral March, and he certainly couldn't use that. He didn't think he could transfer any of Carter's collection of arias to the organ, and if he did all Slytherin House would know who had done it. That would never do. Perhaps the Great Organ Cliché by Bach would suffice, if he could figure out how to spell it into the instrument.

Severus also doubted the instrument was in working order. Repairing and cleaning it, without making it look any different from the outside, would require several Filch-free early mornings. Those could be arranged.

A month later, as the ceiling took on an early-morning glow, Severus slipped back down to Slytherin's dormitories to pretend he had just awakened. All was in readiness. He regretted only that there was no way to test his work without alerting everyone in the castle. Bach's 'Toccata and Fugue in D Minor' would now be triggered the instant Lily set foot in the Great Hall, hopefully, and Severus now knew a dozen new spells pertaining to instrument repair and music. He'd even attended a Slug Club meeting to pinch Slughorn's book on tuning keyboard instruments, and would have to attend another to put it back.

Back in the Great Hall with plenty of Slytherin company, Severus was helping himself to eggs when Lily entered, pesky Potter at her side. The organ coughed to life right on cue, blasting forth its colossal sound and a cloud of dust and spiders. The Head Table took the brunt of both, but the growing cloud billowed to fill the room. Lily stopped in the doorway and shot an amused, accusing glance at Potter, who looked far too bewildered for guilt. Severus turned his attention to the staff before she could move on to accusing him.

McGonagall was shielding her teacup, Sinistra and Flitwick were sneezing, and Dumbledore was drawing his wand -- and laughing. The organ played on as the dust suddenly collapsed into a rather large ball in midair and heaved itself out a window. Spiders, live and otherwise, continued to rain down gently. Severus doubted anyone would think to be grateful that he had removed all less savoury items from the pipes and evicted the family of bats.

When the music ended, Carter, across the table, shook his head. "If the point was the music, I have no idea who did it. If the point was a surreal early-morning spider shower for the lot of us, my pick is Snape."

Severus was always amused when people were right for the wrong reasons. He rescued a drowning arachnid with the handle of his spoon. "I prefer sugar in my coffee, thank you."

Rookham offered a particularly large and leggy specimen to Regulus Black. "If you like them." It seemed he did not. She shrugged and deposited it on the tablecloth between them, and he edged away. Severus noted the reaction for later use.

In fact, this was an excellent time to pick out the school's arachnophobes. Clothos Ketterly, seated by Rookham moments before, was nowhere to be seen. Davey Gudgeon of Hufflepuff seemed unusually anxious, combing out his hair with his fingers repeatedly and shivering. Neither Potter nor Pettigrew seemed to have much appetite, and Pettigrew looked distinctly out of sorts.

"Spotting the guilty party?" Rosier asked.

"Not successfully. I believe most of the musical types were sorted into Ravenclaw, however."

Rosier nodded. "It was an awfully brainy sort of joke."

Severus gave ten points to Snape House for the indirect praise. This year he had overtaken Ravenclaw for the House Cup in his little game. Of course, self-scoring did give him something of an advantage. "Probably Quesenberry was trying to prove something to Potter."

There. He had quietly implied that he thought the organ had been Transfigured in some way, and this was now going to be taken as fact because he was known to have an eye for spell identification. This presumed fact would then shift suspicion from Severus, who was known to be rather better at Charms. The idea seemed well-planted.

---

Lily didn't get the chance to comment for two more days, when they could finally sneak off to work toward their impending Potions N.E.W.T. "Nice one," she said rather dryly, setting up her cauldron.

"Pardon?" He was now in the habit of pretending to have had nothing to do with the whole matter of the organ, and had momentarily forgotten what she meant.

"I thought if I had one friend I could count on to not make a fuss over my birthday..."

"Only because you did not tell me when it was. There were six years of neglect to repay."

"Well, you succeeded." She laughed suddenly. "And outdid last year's Gryffindor Quartet while you were at it. Only Sirius can sing at all."

He thought the foursome might have been bad enough that even they had noticed; they had not repeated the performance this year, at least not where anyone else could hear it. "My apologies for the dust. I did clean out the dead mice and live bats, at least. And the droppings of both."

She gave him a sideways look through her hair. "So the spiders were deliberate?"

"The spiders were for everyone else. If I had taken those and the dust, Filch would have noticed that something in the Great Hall looked different, and the game would have been up. But the other things seemed a bit -- unsanitary, perhaps? -- and excessive."

"Very considerate of you."

"As always. Happy birthday."