Try changing your tail in other ways.

You're already on a roll here, discovering more and more things your tail can do, that you figure why not keep experimenting? One thing that occurs to you is that if you can make your tail any size you want, and bend it into any shape you want, you can probably reshape it in other ways too. Your attention is captured by a fly buzzing around your room. Normally this would be nothing more than a minor annoyance, but being part cat, you feel a sudden urge to chase after it. Though rather than running after it as instinct would have you do, you decide to see how your tail can be of use here.

Just for the hell of it, you make your tail real long and thin, and try shaping the end into the head of a fly swatter. As you consider how to do this, you give the end of your tail a little shake, and much to your elation, it instantaneously takes exactly the shape you were picturing.

Sophie: "Coo-oool! Now where did that little bugger get to..."

Looking attentively, you eventually spot the fly on a wall on the opposite of the room. You go to reach out with your fly swatter tail and swat the thing as fast as you can, and shockingly, it all happens in the blink of an eye.

Sophie: "Whoa...I'm fast!"