Despite the fact that paintings and drawings generally did not face the same legal restrictions that frontal nude photos did in the 1940's and 50's, Quaintance frontal nude art is very rare.  His usual practice was to go ahead and do a version with the package fully showing and then paint over it.  The idea was that the work would be more realistic that way, and I can't argue with the result.  He also did fully nude pencil drawings as studies for some paintings, but only a few like this one survive.