Regular poster, NC for this.
There is a colleague I encounter at work most days.
Almost every time I see him he compliments me hugely and squeezes my shoulders (often from behind, both hands).
He definitely goes out of his way to touch me if our paths cross - though not in an overly inappropriate way or place - but it's definitely a habit.
Not one I reciprocate or encourage (in fact I will often go out of my way not to speak to him because of it.)
He definitely is NOT attracted to me in any way, and he makes no effort to do this surreptitiously - he will do it openly in front of other colleagues, junior and senior, in a crowded room.
I am definitely very much unavailable, and he knows this, as does everyone else.
What on earth is he doing?