Yep, so it originally occurred directly after I flushed the toilet while the cat was beside it. I attempted to replicate it on a second playthrough, but it didn't occur. It was corrected by repeatedly doing the tasks for the black cat up until the full sink, but without the TV. When they met at the bathroom door, they would meld again, first so there were two, then leaving one. I was able to complete the game normally afterward.
