Warning: when using a small litter pan (like this freaking 9 inch disposable turkey roaster!) be prepared to clean it at least 3 times a day.
This morning, before I had a chance to clean the litter box, I caught Pascha as she discovered the dirty litter box, only to change her mind and hop into the bathtub. I saw her pawing at the drain and I knew what was coming. So I quickly cleaned the box and placed her in it. She did not like the idea of being back in there so she hopped out, lept instead into the sink and proceeded to pee there!!! I didn't know what do do so I waited. I thought she was finished but she raised herself like she was going to defecate. I picked her up up gently and placed her into the now-clean litter box, but she lept out and instead pooed on the floor in the corner of the bathroom.
I feel defeated. And now I have a lot of sanitizing to do.
But the good news is that eventually we won't have this problem. This would have happened to any dirty litter box and the difference is that before this small one I had an enormous one that only needed to be cleaned once a day. Nine inch turkey roasters are not suitable for 2 cats.
This does, however, reinforce the notion that the cats just want to go to the bathroom in a sanitary, smell-free place. I'm pretty sure Pascha will be happier when she won't ever have to worry about dirty liter pans again.
By the way, if your cats do this then please do not, under any circumstances, scold them. I wanted to so badly and in fact I did ignore Pascha for a little while afterwards. Ignoring is not the same as scolding (blowing off steam is more like it!), and negative reinforcement just does not work with cats. In reality, any human would have done what she did. I will make sure to praise her wildly next time she uses the litter box. Wildly.