Dan stood there, a 16-year-old fox-girl, looking with fear at his/her older sister. "Wh-why are you d-doing this?" she asked, voice trembling and tail swishing.
Kat smirked. "Because," she said, "I just figured out some spells relating to inter-dimensional transportation and time dilation, and I want to try 'em out. I managed to scry out a universe where the dominant life-forms are anthropomorphic animals, like you are now, and I'm going to have you check it out for me. The time dilation part comes in when I cause your trip through that world to take a mere billionth of the time in our dimension that it does there."
Dan whimpered. "Then I...I..."
"That's right," Kat giggled, "you're going to spend an unspecified number of years there. I'll bring you back before Mom and Dad get home anyway, though the exact amount depends on how quickly you sight-see enough to satisfy my curiosity, and how many...interesting experiences you have there."
Dan whimpered again, a very non-human and clearly vulpine whimper. "But wh-why am I a...a girl?"
Kat smirked again. "Because I said so, stupid. And don't even think about ratting me out when you get back, or I'll send you packing to a worse place, for good."
"Pl-please..." Dan's soft, feminine voice was barely more than a terrified whisper.
"Enough!" Kat snapped. "It's time for you to go, Danielle. Don't worry, I'll alter your mind to speak the language, and I'll be...keeping tabs on you." She didn't break into evil cackling, but Dan had a feeling she might, at any minute. Kat rose, pointed one finger at Dan, and the world went black.