Severus Snape-Cat

It began not with one mistake, but with a symphony of them, a cascading failure of incompetence that unfolded with the dreadful inevitability of a Greek tragedy.

Snape’s eyes, perpetually scanning for idiocy, caught the first sign: the Longbottom boy, his face a mask of panic, was frantically stirring his Shrinking Solution counter-clockwise. The brew was already a sickly puce. The second movement in this opus of imbecility came from Miss Parkinson, who, in a fit of pique at a Gryffindor’s successful potion, had clearly over-crushed her scarab beetles, introducing a coarse, unstable grit into her mixture, which now bubbled with an oily, menacing sheen.

The crescendo, however, was the Weasley twin—Snape was certain it was one of them, though which pest was irrelevant—who, from the back, decided this was the perfect moment to test a "jelly-leg" jinx on a Slytherin. The jinx missed. It struck a Hufflepuff's cauldron stand instead, the very cauldron containing a poorly filtered Strengthening Solution. The stand buckled. The cauldron tipped.

Time seemed to slow, granting Snape a perfect, horrifying view of the disaster.

The Hufflepuff's thick, gloopy Strengthening Solution sloshed across the aisle. A great gout of it splashed directly into Longbottom's violently bubbling Shrinking Solution. The two magics, one meant to compact matter, the other to fortify it, created an instantaneous and violent reaction. The puce potion flashed a blinding, acidic yellow and began to expand, not explode—expand—like a malevolent, rising dough.

This expanding cloud of chaotic energy collided with Parkinson's over-pressurised, grit-filled potion. The scarab grit acted as a catalyst. The unstable oils in her potion ignited.

The result was not a fire, but a transformation. The three distinct magical reactions—shrinking, strengthening, and combustion—sublimated into a single, roiling cloud of iridescent, peach-colored gas. It did not explode outward; it bloomed, filling the entire dungeon with impossible speed, carrying the combined, corrupted properties of all three botched brews.

Snape had his wand out, a Shield Charm on his lips, but the gas was not an attack to be blocked. It was a state change. It passed through his magical barrier as if it weren't there, and the world dissolved into a tingling, warm, peach-colored mist.

The sensation was appalling. It was a thousand needles pricking his skin, not with pain, but with a bizarre, unwelcome activation. He felt his bones hum, his skin crawl. He heard not screams, but a chorus of startled, high-pitched yowls and confused mews.

As the gas settled, pulled away by his own furious and automatic Vanishing Charm, the scope of the catastrophe was revealed.

His entire classroom was a tableau of absurdity. Perhaps two dozen students were in various states of felinification. Some sported ears and tails, others were covered in patchy fur, and all were staring at each other in confused horror.

He looked down at his own hands. They were obscured by the sleek, black silk of his robes, which now seemed... fuller. A profound, unnatural sense of balance settled over him. And then he felt it. A weight. A twitch. Two velvety, pointed ears had erupted from the top of his head, swivelling independently to capture every panicked breath, every whimper, every stupid, stunned thought in the room.

A low, rumbling sound started in his chest. It was a growl. A deep, furious, and utterly involuntary growl of pure, unadulterated rage.

His black eyes, now slit-pupiled and even more menacing, swept over his transformed classroom. His voice, when he found it, was a terrifying hybrid of his usual silken threat and a hair-raising, feline hiss.

"Out*..." he spat, the word laced with a promise of unimaginable retribution. "Every last one of you... vermin... TO THE HOSPITAL WING."

He would skin the Longbottom boy for his potion-making book. He would have the Weasley twins expelled for this. But first, he had to navigate the hallway to the infirmary without chasing a stray beam of sunlight or trying to bat at Peeves with his new, unsheathed claws.

The humiliation was absolutely beyond conceivable description. And the growl in his chest would not stop.