But her "Duo partner" looks ok, so why the need to fuck the client around ?
Err, Pass! Maybe they work out of the same apartment and they double booked, or the other decided to pop out for fags... I think where there are a pair of girls working closely with each other they seem to develop a blase attitude to service - "you do this one, I'm just popping to get some shopping......", on the basis that very few clients will walk away. So, rather than "bait and switch" its more like "your getting a fuck, what's it matter who its with"
I had a similar experience a long time ago where I arranged to see a very fit 23yr old, in the days before AW, really good reviews etc., I got there and she opened the door and said very apologetically that she had to go out but her sister was up from London and could see me instead. My thoughts were "here we go" and then her sister appeared to say hello and she was just stunning. Saw her quite a few times and never did get to see the other one!