Hands that instinctively cower in pockets during high anxiety, social encounters.
While some men possess wolf-like prowess around the ladies, others become overwrought with feelings of inadequacy and experience scaredy pants hands and generally finish off the night that way.
The act of pleasuring a man while his pants are still on. Hence "over the pants" it's generally very difficult to master as the penis is hard to get to. You're better off to take his bottoms off and just give him an actual hand job. It's more pleasurable.
I gave Alex an over the pants hand job last night, he needed new boxers when I was done.