Ahah, I forgot about Moondoggie's reaction. He screams like something horrible has happened, and then you see him cleaning too.

I always thought the changes in Eureka's red circle was because her eyes were either wide open, or some variation of half-lidded. Interesting theory though. Do Anemone's change their angle relative to flat? It should be easier to tell because the mood-swing queen changes about 10 times a minute.

As for their two particular shapes, it's neat to note that a circle and a line are about as opposite as two objects can be. One implies completeness, and the other does not. (This is kinda obvious, but I felt like pointing it out.)

I like the idea about the exchange with Eureka and Renton, but I always got the feeling that something worse than that happened to Diane. They didn't seem too emotional about the Coralian, as if something bad like that had happened before, more that they just wanted to make absolutely sure they got into it first.