I can remember seeing this 4 times. Interestingly, 3 of those 4 ladies were Asian. The first time I noticed a woman clearly wearing a functional key on a necklace was in a supermarket in Switzerland in 2010. There was a blonde, very beautiful girl clearly playing with a real key on her necklace. A few moments later, her boyfriend showed up and the kissed very intimately. In 2014 I worked at a university in Mongolia. 80-90% of the students at the English Department were female. On the first day, I saw a female student very clearly wearing a functional key on a necklace. The key looked similar to the one worn by Lady Jezerae. I got very excited, but didn't dare to ask what the key was for. Unfortunately, she was not one of my students, and I never saw her again. In 2016 I saw an Asian woman at an airport, I can't remember which one exactly (possibly Munich), who was wearing two identical, clearly functional keys on a fabric bracelet. The last encounter was in Mongolia again. Only recently, about 1 or 2 months ago, I saw that the lady working at the till of an Indian restaurant had a real key dangling from a silver bracelet. It reminded me of a certain version of the CB-6000. I was more excited than ever before, but again didn't have the courage to say anything. I really wonder whether the key just has a different meaning or male chastity is actually more common in Asia.