Very cute. I've read a couple 'Kaylee hides a cat' stories but this one was original enough that it didn't just feel like reading one of those again. (Is there a challenge somewhere about the crew hiding a pet from Mal? It seems to pop up a lot.)
The Jayne pov was well done and I really loved the score keeping by River - her warrior comment made me laugh out loud. It's just like a cat to spend lots of time with the person who really doesn't want it around.
My only critique is the word "sqoze" towards the end. Is this a typo? I'm pretty sure it's not a word, you probably should have used "squeezed".
Maybe the word "squoze" is a regional thing; I use it for "squeezed" all the time, and it seemed like a Jayne-ish word to me. shrugs I don't know of any challenges out there for "hiding a pet from Mal fic;" it was just a rabid plot bunny that bit me on the ankle and demanded to be written. Glad you enjoyed it. :-)