This reminded me of how much I dislike being hugged from behind. I really prefer knowing who it is first.
These years, I could probably pull my act together to pull away or say I don't like it, but in the past, there've been a lot of times when I didn't have the mental bandwidth or other resource to be clear on the subject.
So, how do you feel about being hugged or massaged by someone you didn't see before they started? Do you give a general permission to some people but dislike it if there's no prior permission?