My take
I've had several experiences, and they've always been mutual.
The 'accidental' touch, the nervous energy, the possibility of the unknown.
You know the act itself is non-social, can often knowingly breach personal space and self dignity.
A lot of what goes on between two individuals at that moment is often known by them only. Others can only speculate, some sneaky, high brow gaze wishing they were in my place.
I'm fairly good-looking, respect boundaries, and never initiate something that may induce fear, shame, or insecurity.
For many, the act of initiation may generally be initiated by men, I've had women push their butt knowingly on my crotch, rubbing their breast's on my arm/elbow, many a times in the presence of their husbands/boyfriends.
What's your experience?
Dm