OK, I wanted to do another PV session and was thinking about a double.  

I've done it before.  I get the basic gist of it with one girl.  Lapdance, mutual touching, HJ, and if your lucky, a tad more.  

My question is, what should I expect from a session from two girls.  I don't expect FS at all, but do they, uh, "interact", with each other?

Why limit yourself to PV when you can have triple the fun??? Bi fun and of course tons of fun for you )

Because I like to enjoy what I do.
As a girl who is also a provider, one does not go into this without enjoying the deed.

 
For a doubles session, the two can play with each other, and should!!
If you want to be assured of girl-on-girl, buy a vibrator, it'll be easier for the not-bi-girls to handle girl-on-girl.