A/N:

First thing first, this isn't an HP AU. I'm just using the concept of animagi in my fic. Also they can transform into 2 animals and not just 1. Not all of the characters are animagi btw. I hope y'all like it :) (Also this was originally posted on AO3 in Nov but I forgot to post it here)

She was walking back home quickly. It was late at night, she was hungry and tired. All she wanted to was go to sleep after the long tiring day. College wore her out and her part-time job wasn't helping either. A good night sleep would probably fix her up a bit if not much, that is if she reached home safely. Ever since she left the shop, she felt as if something was following her, looming behind her, stalking her like a creep. She normally wouldn't come out at this time. She shouldn't have agreed to take up that extra shift to cover up for her colleague. She clutched the strap of her bag, trying to convince herself it was just because it was dark and there was nothing else. Why couldn't she shake that feeling away?

She turned around for who knows how many times she had. No one, except for a black cat that licked it's paws, glancing at her with those icy blue eyes every now and then. She had a white splotches fur on the sides of her head resembling stars, a symbol that Mahiru recognised. It was that cat again. She loved cats. Cats were cute and no doubt about this one. However, whenever she turned around the cat was there. No matter when or where it was there, licking its paws, looking at her or looking somewhere else all together. It was evident it was following her or Mahiru was just paranoid which had a high probability.

Mahiru shook her head. She needed to get a hold of herself. The apartment she shared with a friend of hers was close by. She shouldn't be worrying so much.

She entered the dark apartment slamming the door behind her. She heaved a sigh of relief dropping her bag in the floor dropping to the floor to calm down. She hasn't realized her heart had been pounding so hard that made her feel dizzy. Her breathing was laboured. If any one sees they'd-

"Mahiru chan what happened?" a sleepy voice asked. Mahiru looked up to find Karen standing front of her holding a pillow against her chest, rubbing the sleep from her eyes. She barely opened one of her eyes, "Why are you on the floor?"

"I just came back from work and I was-"

"Mahiru chan, don't tell me you took her shift again!" Mahiru's downcasted eyes were filled with guilt. "Non non dayo, Mahiru chan. Let's say the blobs come after you!" Karen said worried. "I know it's not safe but she asked me a lot and I couldn't deny her." Mahiru tried to justify her case. Karen sighed and got on to her knees giving Mahiru a hug. "I don't mind you helping her but please be careful." Mahiru hummed in response. She can only try her best.

After some dinner and a nice bath Mahiru plopped on her bed, scrolling through the unread messages on her phone. Most of which were Maya and Junna's discussion on the chat group about the increase of deaths in their locality due to those caused blobs.

The blob was a failed science experiment at the nearby science facility. It was originally designed to clean the earth from garbage and pollutants but instead it turned against humanity, eating humans instead. It was literally a greyish black mass that formed and hissed as it crawled on the streets mostly at night for some reason. It caught it's prey by using pseudopodia. Apparently if one were to be in contact with one it would never let go of you till it completely consumed you unless it died before you did. The worst part it grew stronger with every human it ate and also had the ability to reproduce. Also it moved fast to catch its prey. On the bright side it's sense of smell was on the level of whale. It was indeed a spawn of the devil.

Thankfully there was a ray of hope in these darkest of times. A minority of the population known as animagi who had the power to transform into animals. Or more precisely they can transform into two animals, one in their normal state and the other when they feel intense emotions like anger. In their human form they are as susceptible to the blobs but in their animagus form they can fight them and destroy them for good.

It was a long day and she could feel sleep pull her her eyelids down. She might as well just call it a day. She pulled the covers over herself it's warmth soothing her. Ah, how she loved her bed. She turned off the bedside light, the room now bathing in darkness. She let out a content breath drifting off to sleep.

Or at least she was supposed to.

A scratching sound came from the curtained window of her room. A repeated sound that sent shivers down Mahiru's spine. What was it? Mahiru shivered as she sunk into her sheets, in hopes that it would protect her as she tried to sleep. The painful sound didn't stop. She had to take things up in her own way.

She slid out of bed and went to the side of the room where her favorite cat mascot stood holding her trusty baton. It wasn't like any other baton. It was specially made for her given to her by Maya, Kaoruko and Futaba for her birthday. Never had she been so grateful for such a present. Mahiru pressed the top of the baton and it began to transform into mace. Whatever it was it was going to pay for she was good at welding it.

She took careful steps to the window, opening the curtains, letting out a battle cry. Instead she was met by that cat again. That very cat that followed her way back home. She sighed in relief again. Poor cat was left all alone in the dark and she hadn't really bothered to notice then. She may as well give it a place to stay at least for the night. She opened the window. "Hey there-" the cat screeched, the fur on it's back standing straight, and ran away. "Wait come back!" she helpless watched the cat run away. She didn't mean to do that.

She yawned as she closed the window. Boy, she really needed to sleep.

It was that cat again, licking it's paws once again looking at her mockingly as she ran for her life. She stumbled into the nearest street not daring to look behind her, ignoring the presence of that cat. She should have listened to Karen when they told her not to take up her colleague's shift. This was life. It had been tough for everyone and this was just a part of it. Just that Mahiru's was probably about to end any moment in a very verypainful way.

And to her luck it was a dead end. Huge fense that may take her a long time to scale was infront of her. Even if she did get past it, it wouldn't stop the blob. Why did it have to end up like this? She froze, gulping looking behind her terrified. She scratched out the idea of getting out of the street as she saw the vicious creature moving towards her menacingly.

Mahiru's grip on her bag loosened and the bag dropped on the floor. She let out a shaky breath. She never expected to die in the hands of a blob and that to in a alley with a dead end. She had no choice but to accept her fate. She closed her eyes, hearing a loud roar in the surrounding before drifting off into a plane of darkness.

The next thing she knew was in her room. Lying down on her bed, looking up at the ceiling, a cold wet towel on her forehead and a cat purring in it's sleep on her chest. How? She didn't know. It didn't make sense. Was she dead? It had to be. She was face to face with a blob!

"Ah, Mahiru chan, you woke up!" a familiar voice, Karen, said beside her. "I'm not dead?"

"Uhh, no…" Mahiru was confused, "How did I get here?"

"This cat," Karen pointed to the sleeping figure,"it woke me up by scratching my curtains up and asked me to follow it. You were laying in a street covered in blob goo. Then I carried you home." Karen said, proud that she could carry Mahiru, "The cat didn't leave you even after I laid you here and you like cats, right Mahiru chan? So, I thought it was a good idea to keep the cat."

"So that explains why I have a wound on my elbow and the room's a mess." Mahiru examined her right elbow covered in bandages. Karen was shocked. Mahiru did not make a big deal of the messy room. Karen decided to avoid that topic. Cleaning with Mahiru was a bit stressful.

"I'm sorry I didn't mean to drop you!" Karen clapped her hands together in forgiveness. "It's fine, but…" Mahiru wore a scary expression on her face. "Karen chan, did you forget to close the window before you went to sleep?" Karen, terrified, nodded truthfully, unleashing the inner demon of the normally timid Mahiru. Mahiru was just worried, let's say Karen got sick, Mahiru's heart wouldn't be able to bare the sight.

"I won't do it again." Karen said, almost tearing up. "Now, this cat, what do we do about this?"

"Can we keep it? I've always wanted a pet." Karen's eyes shone. "I thought you were a dog person."

"Cats are fine, I just want a pet. Also Mahiru chan you like cats. Can we keep her please?" Karen was now making puppy eyes making it hard for Mahiru to deny the request. Sometimes her friend was too cute. "Fine." Karen cheered in excitement waking up the poor cat, making Mahiru angry at Karen once again.

A few weeks passed and the cat became a member of their family. Her name or at least what Karen wanted to keep was Hikari as it looked similar to her childhood friend. According to Mahiru it was a perfect name that complemented her star shaped splotches of fur on her head. Also it was a light in their lives in thier monotonous life. It was a lot of work but Mahiru took care of her like a baby, or at least tried to. Like taking billions of picture of Hikari or when when Hikari dirtied the clean room while playing she chided her. But she enjoyed it anyway.

Mahiru rolled out of bed ready to start the next day. She opened the bathroom door sleepily, but that sleepiness didn't last for long. It was wiped out by one of the most bizarre sights that would make one think it's a dream. A girl; a naked girl was sitting in her tub, bathing. Her long black hair was tied to prevent it from getting wet and her blue eyes stared at her emotionlessly. "Hi.", her deep voice resonated in the quiet room. A loud scream pierced through the air before Mahiru fainted due to overheating.

Mahiru didn't understand even if a few days since the incident had passed by. It didn't make sense. How did her beloved cat end up being an animagus? Being an animagus was fine in her opinion, it was in fact cool. To be able to perform such an complicated spell without any terrible outcomes to get the most useful weapon that was required in their times needed gut, guts that Mahiru didn't have. But to deceive them was very bad of her and if she ever saw her again she was going to get a mouthful even though she was very grateful she had saved her life.

"Mahiru chan," Karen's overly cheerful voice broke her out of her reverie. Karen had finally come back from shopping after an hour. It was a huge improvement. The last time it three hours, Mahiru freaking out to only find out she had gone to the arcade forgetting what she was supposed to do. Karen threw the groceries on the floor but before Mahiru could chide her for doing so Karen had already flown onto her lap, overflowing in joy, even more than usual. Karen's contagious smile had spread to Mahiru as Karen exclaimed,"I met my childhood friend today at the supermarket."

"Really!?" Mahiru's little pigtails swung in curiosity. "That's right! I met Hikari chan at the store. She hasn't changed one bit."

"That's nice."

"I called her for lunch tomorrow, I can't wait!"

Mahiru was not mentally prepared to meet a new person. Sure, Karen had told her story upon story about their childhood till they had to go on their separate paths, there was even a framed picture of the two when they were young in Karen's room but to meet so soon! "But Karen chan, does she need to come tomorrow? The house is not in a very proper shape and-"

"Mahiru chan, no need to worry. She's a nice person."

The next day arrived sooner than Mahiru expected wanted to. Karen was fired up and determined more than anytime she had ever seen her. It was a new side of her completely. She was ready to help Mahiru set up everything ready for the guest. From the house being squeaky clean to the food on the table. Mahiru was totally fine till she heard the doorbell ring. Nervousness seized her as she stood in her place dreading to meet her. "I'll get it!" Karen sprang up from the sofa and rushed to the door.

And the door swung open. Mahiru couldn't see the person properly till Karen moved aside as she chatted away rapidly to the quiet person at the front door.

And that person was... her…