It’s no surprise that the Motion Picture Association of America rates movies, but who knew they also approve (or disapprove) movie posters?  That’s apparently what happened to one of the character posters for Sin City:  A Dame to Kill For, which was disapproved for content, according to the New York Post. 

The first five posters were released earlier this week, and included Jessica Alba as Nancy, Joseph Gordon-Levitt as Johnny, Josh Brolin as Dwight, Mickey Rourke as Marv, and Rosario Dawson as Gail (see "Character Posters for 'Sin City: A Dame to Kill For'"). 

The Eva Green as Ava poster, with the apropos blurb "I’ve been especially bad," was banned by the MPAA for "nudity' for the sheer gown, according to the Post, which also reported that Dimension Films and the MPAA were discussing a compromise version.  

Although at this point, it would seem the banned version has probably already done what the studio wanted regardless of whether or not it's ever displayed in theater lobbies.  

The film will open August 22 (see "New 'Sin City: A Dame to Kill For' Trailer").

And yes, you can click the poster for a larger view.