From what I could get I have been accused of being obscene and they kept asking if I was making hand gestures. I disnt gestire anything or talk about sex or anything at all. I dont know wtf this person is talking about!!
Sounds as if someone was ease dropping and wanted to play on the fear of the "me too" movement to get back at you for whatever reason.
If HR does a proper investigation, your appropriate work conduct will speak for itself. Other co-workers will stand behind you, if given the chance. I hate this type of backstabbing mess!
It is not about what you feel should work in your M. It is about doing the work that gets the right results. Do what works!