This was going to be great. Doug had been waiting so long for this package to arrive. So many days spent searching, so many nights wasted on dead ends. But finally, finally he had found his goal. A catgirl of his very own. They were super rare and, partly illegal, but oh it would be so worth it. Not only would she get rid of that damn mousegirl, but give him the perfect pet to come home to. Oh yes, the massive amount of cash and potential trouble with the cops was worth it.

Finally, the delivery man arrived. The large crate was wheeled out, the signature given, and Doug was left alone with his newest treasure. He pried open the box, eager to see her and... And something less than ideal emerged. It was a catgirl, of that there was no doubt, but this one...this one looked more like a young child! This wasn't the deal! She was supposed to be full grown!

The catgirl stumbled out and blinked a few times. She smiled at Doug and began to rub against him, but Doug was too busy being furious. Dammit, NO! He had paid too much to get shafted like this! He moved away from the girl and snatched his cellphone up. That son of a bitch was going to get it!

While he and the seller began to scream and curse at one another, the catgirl decided to explore a bit. She wondered around, smelling a few things and doing her best to try and get into trouble. She started to mess with a bottle of some kind but couldn't get the thing open. She started to go back to Doug to see if he would play when her nose caught something. She whirled around and licked her lips as she noticed a tiny figure moving through the kitchen.

The mousegirl hadn't yet realized the threat Doug's new pet brought. She was just hungry and knew the pantry contained food. She started to try and slip in when her ears picked up a sudden scrap. She and the catgirl froze for a moment as if daring the other to move first. The catgirl dared and sprang forward only for the mousegirl to dash under her. The catgirl whirled around and swiped at the mouse, but she managed to leap over the grab. The mouse tore off at full speed and slid under the fridge as the catgirl slammed into it trying to catch her. She pawed under the fridge, but the mousegirl was long gone retreating back into her nest.

By then Doug had been hung up on and realized that he wasn't getting a refund. Worse, he was now stuck with the young catgirl. They did grow much faster than humans, but it would be months before she was old enough to not make him feel perverted. Worse, she was still in her curious phase and would be a nightmare to leave alone.

Still there was little he could do as just kicking her out would all but doom her to death. He was stuck and that was all there was to it. At least she had gotten on with the task of hunting that damn mouse. He headed to the fridge, shooing the girl away so he could open it, and began to look for some food for her. With her prey gone, the catgirl wondered back into the dining room and to the bottle again. She tried to mess with it some more, but her play was stopped By Doug. He snatched the bottle away and told her not to touch it.

The bottle had been another poor choice. It was supposed to help plants grow and Doug had planned to use it to make a garden. Instead all he got were weeds the size of stumps... Damn thing caused growth all right, just not to the rig...

Doug looked at the bottle and thing looked at the catgirl. No it was crazy, but if it worked... It HAD made those weeds grow, but those were WEEDS not catgirls. No, this was madess...but then who the fucked cared! Worse came to worse this whole mess would sort itself out, as horrid as he felt thinking that. But his conscious didn't stop him as he took the top off the bottle and called the catgirl over. He gave her a small sip to try at first, no reason to go overboard.

To his surprise, the catgirl looked to enjoy it and licked her lips eagerly. She made it clear she wanted more, but Doug figured this was enough. He might want to dump this stuff onto someone else at some point. Doug let her nuzzle on him in thanks and watched for any sign of her changing. After a few minutes of cuddling, though, she was still shrimpy and small. Ugh why had he thought that would wo-

Wait... was she...yes YES! She was changing! The catgirl gave him a confused look as she stood up before looking down to see her move away from the floor. Doug leap to his feet and watched as she rose past her chest and to his chin. Every second seemed to cause another spurt and her height and age increased. Her small chest expanded into true breasts while her hips spread and widened. Within less than a minute she looked like a proper catgirl and it was all Doug could do not to take here then and there.

But this needed some prep work and so he rushed off to his bedroom. The catgirl watched him leave before glancing down at herself. She didn't understand what was happening, but it felt good! In fact, the good feeling was coming back! She watched as the furniture became smaller and her head moved closer and closer to the ceiling. Her lower regions began to itch and groan with need and she followed Doug into his room. Doug was still getting his bed cleaned off when the catgirl entered the room. He turned to shoo her out, but stopped dead when he noticed he was level with her chest. A chest that was far larger than it had been. He, slowly, looked up and the catgirl smiled down at him. Before he could fully react to what had happened, she snatched him up and tossed him into the bed.

Doug had enough time to recover before she was on him. She pinned him to the bed with ease before one last spurt coursed through her body. Her tiny child-like form was now long gone to be replaced with a 12+ foot tall amazon. The catgirl planted a long kiss on him before moving her pussy to hover over his erect penis. She let out a purr of joy before sliding him in.

While amazonian catgirl and lucky man began to make love to one another, the other being in the house was putting her plan into action. The mousegirl had watched the catgirl's sudden change and had put two and two together. Having stolen a bendy straw from a cupbeard, the mousegirl lowered the straw and began to drink. And while nothing happened at first, it wasn't long before the spurts the catgirl had began to grow the mousegirl bigger and bigger, and bigger. And she wasn't going to be happy till she was the one chasing the catgirl into hiding.