On Fri, 9 Aug 1996, Wombat Master D wrote:

What *is* the frame story?

Somebody is manipulating time. Or rather, TWO someones: Green Robes and
Purple Robes. They've been doing things by responding to people's
wishes... and setting up different timelines. 

Mmmm...  I didn't see it that way.  Green Robes is setting the timelines
up, but only because he's being told to by Purple Robes...

Now as to WHY they're doing that... is going to have to be answered as
soon as I finish the Kunou elseworlds and whoever was supposed to do the
Ranma one finishes his. ^_^

...Purple Robes is giving away wishes to remove people from the 'real'
timeline, and so prevent her father's death.  (Yes, I think Purple Robes
is Akane.  And Yellow Robes is Nabiki.  And of course, Green Robes is
Gosunkugi, but I'm fairly sure we're supposed to think that.)