From what I’ve read about these two, both ladies were very bright and both had a keen sense of humor.
Some may have called it a sense of mischief.
Marlene was fluent in several languages, similar to many people from Europe. When she was learning common American expressions, Marlene express surprise and disdain for those who say “I know...right?” “I can’t believe that he talks like that. That’s bad English!” she exclaimed in a phone call to her film director.
Dietrich was one of Audie Murphy’s lovers. She also had relationships with Patton and James Gavin. She was fascinated with American soldiers. Murphy and Dietrich were overheard at the Brown Derby deep in, not a romantic conversation, but discussing US/German ground combat and command and control zt various levels. Murphy kept asking her detailed questions about Patton, she kept peppering him with questions about squad and platoon level infantry combat and differences between German and US tactics. As all this was in process Dietrich was giving Murphy a very intimate thigh massage as he was trying to get a good look at her tits.