Hmm, yeah the interrelation of Tokimi, Tsunami, and Washu is prety 
interesting, and that's one really fun way of handeling it.  Just for fun here's 
a really silly alternative
	Well start with the trio creating the universe, except once it's created 
it's mostly self regulating.  So while it took all three of them to create 
reality, maintaining it is a one goddess job.  So basically two godesses assumed 
mortal forms for a few milenia while one maintained the universe.  The reason 
Tokimi wants to see Washu is because thanks to her amnesia she's forgotten it's 
her turn to become the Goddess and let Tokimi have her fun in the mortal realm. 
 (This concept is to light)