The rise of raunchy, female-centric sex comedies (Bridesmaids, "Whitney," "2 Broke Girls," "Girls") continues. Former college frenemies Lauren (Superbad's Lauren Miller) and Katie (The Sitter's Ari Graynor) move in together and start a phone sex line. (Do they still have those?) This low-rent "Sex and the City" doesn't aspire to much more than being cute 'n' filthy--but it at least fulfills that promise. 85 minutes R.