Killer Joe was originally an off-Broadway play starring Michelle Williams. Michelle played Dottie in the original production and did a full nude scene every night. Dottie is now played by Juno Temple in the movie and she too does full nudity.
Juno wears lots white tops with no bra throughout the film so lots of see-through action. About 12 minutes in, Juno appears in a vision fully nude and then does some kung fu moves before disappearing. Half an hour into the film, there is an overhead shot of Juno’s breasts as she changes in a dressing room. And at 41 minutes, Juno very slowly removes all of her clothes and stands nude for a bit before putting on a dress. Juno then bends over toward the screen and hikes up her dress so we see her bush as she is having sex.
Speaking of bush, the very first time we see Gina Gershon, all we see is a closeup of her bush. Only two minutes into the movie, Gina answers the door bottomless and then walks around a bit before finally putting something else on. Then at 51 minutes, I think we get another brief peek of Gina bush as it looked like she was bottomless again.