A/N: I couldn't get this idea out of my head, so I took a little break from writing my other story. I personally don't like cats, but I like the intelligence Ms. Norris seems to display. I hope you enjoy my weird little brain.

The students at Hogwarts School of Witchcraft and Wizardry had many differences, hair color, height, age, blood status, and house that set them apart from each other. But they all could agree when it came to one thing; their equal dislike for the caretaker, Argus Filch and his feline companion, Ms. Norris.

Argus Filch was a bitter old man, who stalked the halls scaring off any student that dare break a rule under his beady-eyed watch. He was constantly making first years cry, and second years wet their pants. The older kids had learned to steer clear of him, but every so often they were scared witless when he would suddenly appear from behind a painting and catch them breaking rules.

There were many rumors surrounding the caretaker. Some people thought that he was an ex-con from the States, and was hiding out in the castle. Some said that he was Dumbledore and Madam Pomfery's illegitimate child. Others think that he was an ex-dragon tamer, and Ms. Norris was really a dragon in disguise. Most just say he is an angry Squib that hates magic and children. Like most rumors, none of them were true.

Argus Filch made his way into his office rubbing his aching shoulder. He had had the misfortune of cleaning up spilt dragon tears in the dungeons earlier in the day, and some hyperactive third year had bumped into him, making him slam his shoulder on a nearby cauldron. He knew he should go report to Madame Pomfery, the school Medi-Witch, but in all of his sixty-five years of being the caretaker at Hogwarts he had never went to her to heal his wounds, instead just let them heal the muggle way. It wasn't because she wasn't efficient, or he had romantic feelings for her, no. It was because Argus Filch had vowed when he was ten years old, that he would never again use magic, or have magic used on him.

He sat down at his desk and pulled out a bottle of Firewhiskey that he had confiscated from a seventh year Hufflepuff. He took a swig, and the pain on his shoulder lessened a bit. His door was pushed open and his cat, Ms. Norris, jumped up on his desk, scattering his papers to the floor.

He looked at his beloved cat and sighed as he took another drink. Ms. Norris gave him a sympathetic meow and rubbed against his hand, purring comfortingly.

"Another long day my sweet?" asked the exhausted man. Ms. Norris meowed in response and jumped from the table, padding over to her bed. She turned in circles, then lowered herself into the cushions and closed her eyes.

Argus looked sadly at his sleeping companion, his one friend in the world. Besides Dumbledore, Ms. Norris was the only other being that knew his dark secrets.

That Argus Filch was in fact, not a Squib, and Ms. Norris was not actually a cat.

He closed his eyes that were beginning to tear up at the thought of his troubled past. He took another deep drink of the Firewhiskey, trying to push the memories away. Instead it seemed to make them even more vivid and painful.

"Argus! No! Mommy said you're not allowed to play with Daddy's magic wand!"

The young Argus Filch looked to see his twin sister running across the yard, staring angrily at him. She was wearing her favorite party dress, and had her dark brown hair pulled into two long pigtails.

It was their 10th birthday, their mother had floo'd to go get their cake, and their father was taking a nap before the guest arrived. His father had left his wand on the kitchen table and the young boy couldn't help but grab it. Argus glared at his meddlesome sister and then gave her a wide grin.

"I'm only practicing!" He giggled, waving it randomly at the hedge causing it to sprout lilies. His sister couldn't help but giggle along with him as the lilies suddenly burst open causing golden dust to fly everywhere. She twirled in it and laughed as the dust covered her hair and dress.

"You're going to be the best wizard ever Argus!" She cried happily, catching the dust in her hands and smearing it on her dress.

He bowed and then looked thoughtfully around. He waved the wand at the balloons that adored the tables that were scattered around their backyard and they popped loudly, emitting loud squeals. His sister clapped excitedly, "More! More!"

With a mischievous glint in his eyes he gestured at the table causing it to dance wildly around the yard.

"Let me try!" She said making a grab for the wand. Argus yanked it back quickly and shot her a stern look, "No, you might make mommy's roses shrivel up again!"

"No, I won't!" She pouted stamping her foot, "Gimme!"

"No! I'm playing with it!"

"I'm going to tell Daddy on you, if you don't!"

Argus gave her a threating look, "No, you won't or I will tell him you were the one that ate all the brownies, not Cousin Greg!"

"Please, Argus!" She wined, pulling on his sleeve, "I promise to be careful!"

"No! Go play somewhere else you Squib!"

Her eyes began to water and she turned towards the house, "I'm telling!"

Argus did the first thing that came to his mind, he waved the wand wildly and pointed it at his sisters retreating form. There was a flash of purple light and his sister disappeared, in her place was a brown kitten.

"NORRIS!"

Argus Filch jerked up from his dream and looked wildly around for his bouncy, pigtailed sister. His eyes found his cat and he placed his head dejectedly in his hands.

His sister had been transfigured into a cat, and nothing his parent, the healers, or even the great Albus Dumbledore, did had been able to bring her back. His mother and father hadn't blamed him; they blamed themselves, which in Argus's opinion was much worse. It had destroyed his parents' marriage, they had constantly bickered over what had happen, saying if the other was more attentive then it would have never happened.

Argus was torn apart; he had caused his family so much pain. He had robbed his dear, twin sister of her life, and driven his parents apart. When his letter came for Hogwarts had torn it up and locked himself in his room. He refused to touch another wand, or learn anything that pertained to magic. His parents respected his wishes, but still tried at every chance to get him to learn from them. Eventually he had stopped speaking to them both and just spoke to his sister, even in cat form she still understood him and comforted him. Which made him feel even more terrible that his sister could forgive him for his awful mistake and still love him.

He was twenty when both his parents had passed away. With nowhere to go his parents old friend, Albus Dumbledore, had offered him a position at Hogwarts as a caretaker. He took the job reluctantly; he knew his sister had been excited about going to Hogwarts when they turned eleven. So he brought her along with him, knowing she would enjoy herself more, than at some messy old house with just moody Argus for company.

They were a team to be reckoned with, keeping the halls clean, and punishing any students that had the courage to wonder out past curfew. His sister seemed to thoroughly enjoy herself in the castle, chasing students and mice. He would sometimes catch her sitting in a class watching the students do their work and his heart would clench, knowing that she would be in there with them if it wasn't for him.

Even though she couldn't speak, or write, Argus seemed to understand her well enough, she would curl her tail and glare at him when she was angry, or she would rub up against his hand when she tried to comfort him.

But nothing could ever bring him out of his misery, even his sweet cat sister. He would forever blame himself for what he had done. Even when he was blind, and his memory faded, he would always feel his sister's fur rubbing against him, and he would feel the pain in the deepest part of his heart of what he had done to the sweet, happy girl.