The chunky frumpy chick is the creator,writer,director,craft service,editor,producer,production designer,etc on that show.

She is the 25 year old genius who wrote,directed,produced,starredin some hipster movie Tiny Furniture that no one saw (except Judd Apatow and some morons from HBO). According to IMDB, its theatrical gross was $383,549. It will make more money in licensing fees when it runs on the Sundance Channel ad infinitum in a couple of months.

I am guessing that the series is remake of that movie with a much bigger budget and Time-Warner's marketing muscle.

This is going to be Sex in the City all over again where the lead is pursued by men way over her station in looks and income. The only decent looking broad is Allison Williams, the "best friend".