Nose art by it's very nature was supposed to be racy!
Now if the CO was not the type to approve, you may end up with some really PC stuff on the nose, but for the most part. . .
Also, remember in the WWII era, the Betty Grable pin up was considered a bit on the racy side, and others of topless women were out right pornographic!!
I have a book titled "Aircraft Nose Art" by J.P.Wood. It covers Nose Art from WWI to the First Gulf War, the usually stoic Brits had some pretty mature designs on their Gr1 Tornados!
Don
I know it's only rock and roll, but I like it.