Ally stared at her reflection. She was a dog. No, that wasn't it. Dogs didn't stand on two legs. She was wearing a dog costume. That must have been it. She examined herself for a zipper, running her paws up and down her body, but she couldn't find one.
She noticed something out of the corner of her eye. It was a wagging, fuzzy thing. The urge to chase it hit her. She turned around trying to grab the thing, but it kept evading her grasp. She growled, spinning faster and faster. She landed on all fours, and kept chasing the furry thing. She started barking at it, eager to grab it. Finally, she managed to get a bite on it, and recoiled from pain. She had bitten her own tail.
Wait, her tail? She looked back at her reflection. Sure enough, there it was, curled between her legs. It looked pretty cute on her, she thought for a brief instant, before shaking her head. How did she have a tail? She could feel pain from where she nipped it. Experimentally, she tried moving it up, and watched as it perked up. Her long dog tongue was panting from all the running she had done, and her ears perked up as she realized the truth. There was no way that this was a costume.
Ally suddenly realized her brother was staring at her. Oh god, she was a monster! She was about to run into her room, when Kyle spoke up.
"Ally, why were you acting like a dog?"
She blanched at the question, before realizing what it meant. She hesitantly asked, "Do I look like a dog to you?"
He gave her a look that she couldn't identify. "Of course not. Why would you look like a dog?"
She gave her brother a hug. Her instincts kicked in, and she licked his face out of joy.
"Oh thank goodness. I'm not a dog!" She realized that she was licking him, and stopped. What was wrong with her?
"Easy there sis. What's gotten into you?" Kyle halfheartedly protested. He already knew he was to blame.
"I don't know! I woke up, and now I think I'm a dog. I don't know what's happening to me." Ally was starting to panic.
"If you were a dog, how would you be talking English right now, moron?"
"No! I'm not a full dog. You're the one who's into this stuff. I'm a... what do you call it... I look like an Anthro Dog!"
"Wait. So you think you're a furry right now?" Kyle tried to sound bewildered.
"Yes! I look like a furry German Shepherd named Sadie!" She didn't realize that she had just named herself.
Kyle looked at his sister. Although she was obviously still human, the hypnosis was having an obvious effect. She had run on all fours chasing an imaginary tail, and she had just licked him like a dog. He needed to calm her down.
"Ally, look at me." Ally looked at him, starting to tear up. "You are not a dog. I don't know what's wrong with you but I know for certain you are not a dog or a furry or any kind of a monster, okay?"
She breathed deeply. "Okay. I don't what came over me."
Ally walked back over to the mirror. She still looked like a German Shepherd.
"You're sure I don't have a tail, or fur, or anything?"
"No sis. You're a human being."
"Wow this is weird." She turned back to her brother. "You're not allowed to mention this to anyone, okay? No one."
Kyle shrugged. "Okay, whatever weirdo." He walked into the living room.
Ally stared at her reflection a little longer. If she just concentrated, maybe she could turn back. She glared at the mirror, but her reflection refused to change. She was stuck in this form, although a small part of her brain was okay with that. She looked pretty cute as a dog.
She walked to the living room, where Kyle was channel surfing. "So, what now?" she asked hesitantly.
Kyle looked up at her. "What now? You're the one having a mental breakdown, not me."
He scratched his chin, thinking. "Do you want to act like a dog?"
She scoffed at him. "No! Well..." She imagined herself fetching a stick, and was embarrassed by how happy that made her feel. "Maybe a little bit."
"If you want, I could treat you like a dog. You're obviously going through something weird, and if that would make you happy, I would do it." Kyle hoped she didn't see how eager he was about it.
"I..." The thought of being treated like an animal was appealing to her for some reason. She tried to resist it. "No I don't..."
Kyle was losing her. He decided to use a trigger. "Good Girl, Ally"
Ally didn't hear her brother consciously, but subconsciously the desire to be Kyle's pet grew much stronger. "You promise you won't tell anyone."
"I won't tell anyone Ally." It was good to know he didn't have to hide the trigger any more. That would save him some effort.
"Thank you Master! Oh, but please, call me Sadie. That's my dog name." She was so excited to let loose that she didn't realize she was calling her brother 'Master'. She plopped down on all fours, eager to get started.