A/N: I am not JK Rowling, because if I were, everything I wrote would be geniusly canon.
And okay, I had to do this. Sorry, not sorry. This is based off a tumblr post I saw like forever ago - I'm sorry, I just don't know who to give credit to!
If you asked most anyone about Minerva McGonagall, they would all tell you the same sort of thing: a brilliant witch, a loyal Gryffindor, a fantastic professor, though a bit of a prude. And Minerva was perfectly fine with that common perception, thank you very much. It kept up a certain . . . aura that the professor wished to portray. It commanded respect, and, honestly, when you worked with adolescent, immature boys, you needed to command as much respect as possible.
But, there were certain occasions, certain people that just pushed the dignified Minerva over the edge and, well, it is not wise to push the Head of the Gryffindor House. For when Minerva goes over the edge, she becomes the most petulant bitch ever to roam the earth. Unfortunately, no one ever deemed it necessary to warn Dolores Umbridge of this particular quality when she entered Hogwarts in September of 1995.
McGonagall considered herself a rather tolerant person - sometimes, she would even go as far as to say that she was an understanding person. But Umbridge was a an awful woman who did not know when to stop. So, it comes as no surprise that Dolores, an obvious spy and racist twit, loved to push Minerva's buttons at any chance - not that she had to try hard. With her sickly sweet voice and domineering personality, she would jibe at McGonagall whenever she had a chance, loving the power she had over the Transfiguration professor. Umbridge was a pusher - constantly testing how far she could poke at someone until they broke. And while Minerva was strong, she, like everyone, had a breaking point.
"Is there something you would like to say?" She had asked in that prim little manner, with her fake little smile and her pink little cardigan and bow in her hair. Ohhhhh that bow. If that didn't piss Minerva McGonagall to no end . . .
"Oh there are several things that I would like to say," McGonagall had said as she had her arms around Sybill. She had held her tongue and wand then, for they had been in front of students; it would be unwise to duel with the Minister's right hand with so many witnesses. So Minerva McGonagall stuffed her anger down her throat and let it simmer and coil itself around in her chest until later that day. Once she had let out her classes of the day, petty Minerva emerged.
It wasn't even like she had a plan to what she was doing. She honestly just decided to go find Dolores in her office and fuck some shit up. Remembering herself in a split second before she barged into Dolores' office, she transfigured into a cat and slinked in to the slightly open door. Prowling softly into the room, the first thing Minerva registered was pink. Floor to ceiling, everything was pink and frilly and downright frivolous. Little enchanted cat plates hung on the wall, their desperate meowing showing how they wished to be free of their evil owner. Honestly, this woman's obsession with cats was disturbing, and that was coming from a woman whose Animagus and Patronus were feline. Cat-Minerva's ear twitched in annoyance. It was because of evil people like Umbridge and Filch that cats got such a bad rep.
In any case, Cat-Minerva still had to figure out what she wanted to do to mess with Dolores. She jumped up on the desk, looking around the room for an idea. She was still contemplating when the tiny, stout woman entered the office with a cup of tea in her hand. Minerva froze for a second, before mentally slapping herself. You're a cat, goddammit. She doesn't bloody well know it's you. Easily schooling her feline features into classic nonchalance, she stared back into Dolores' mud brown eyes. The Inquisitor's face broke out into a rare, genuine smile. It looked disgusting.
"Aw, aren't you just the cutest little thing!" Umbridge squealed an octave higher than her already shrill voice. She hurriedly placed her cup of hot tea on the table and reached out to pet Cat-Minerva. The latter slinked out of the way, never breaking eye contact with the woman. Umbridge wasn't fazed grabbing for the cat again and this time succeeding in petting the back part of the back for a split second. Minerva was still figuring out what to do in her head, but feeling the grubby touch of her nemesis spurred her into action. With her catlike grace, McGonagall sprang from the desk to the tall mahogany armoire in the corner. Umbridge let out a coo of delight, thinking that this cat was already fantastic. Well, wasn't she in for a nasty shock.
McGonagall, never breaking eye contact, jumped from the armoire to the little pink couch, landing with her claws out on the pink-tasseled antique pillow, carefully shredding the cloth to ribbons. She picked up the pillow remains and dragged around the floor, letting the goose feathers spew out all over the place. Umbridge's smiled faltered for a second, but quickly slipped back into its mask of adoration.
McGonagall jumped on to the desk and walked across, knocking over every trinket and possession that was on the edge. With each crash, Umbridge's smile flinched a bit, and when finished, the toothy grin in place looked a little fake.
Next, Cat-Minerva leaped on to a side china cabinet. She took a drink out of the crystal pitcher of water before knocking it clean off of the table, along with the kitten faced china. Dolores' manic grin stayed in place, but a few stray, frazzled strands of hair framed her face - cracks were starting to show.
Springing towards the file cabinets, Minerva intentionally opened them and took out every file and tossed them on to the floor with her back paws. The corners of Umbridge's smile started to twitch.
Lastly, Cat-McGonagall jumped back on to the desk that stood in the center of the room. The desk was now clear of anything but the cup of steaming hot tea that Umbridge had brought in earlier. McGonagall pranced towards the cup, and gave Umbridge a look that basically said: What a nice cup of tea there. It would be a shame if someone just . . . tipped it. Minerva had her curled paw almost inside the cup, when Dolores, through her gritted teeth and slightly psychotic looking smile, grunted out,
"Don't. You. Dare." Minerva paused for a minute, her paw still in the cup, and appraised the sight in front of her - by now, Umbridge was barely holding on to her crazy grin, her bow half-hanging from unruly curls that resulted from a hand being run through it too many times. Her pink cardigan was tilted slightly so it looked messy and unprofessional. Minerva contemplated her options, and decidedly took her paw out of the cup. Umbridge sighed gratefully. Then McGonagall stood up, turned around, and took a shit right into the steaming cup of tea. McGonagall took her time to lick herself clean right on the table, jumped down, sauntered cheerily past Umbridge (who still had that fake smile plastered on her face while she stared unbelievingly at the tea cup, as if refusing to believe what happened), and went right out the door. She didn't transfigure herself back into a human until she heard the defeated little scream come from the Defense Against the Dark Arts teacher's office. McGonagall allowed herself a little smile before sweeping off to a meeting with Flitwick about Prefect Schedules.
No chill Minnie McGee had struck again.