Haha, I know what you mean. It seems that almost every girl i put in those table stocks slaps the bench at some point. It must be because their arms are free to move but they still can't reach back and stop the tickling OR get loose.
Ya see the thing about those stocks is that they are not padded so any quick, or crazy movement of her legs can actually hurt and cause pain. I make it very clear to the models before we start that they need to NOT struggle with their legs and ankles or they might hurt their ankles.
So imagine having extremely ticklish feet that are absolutely helpless and being tickled, and you have to hold them pretty much still for fear of injuring yourself. I truly think it tickles more when a person has to concentrate on holding still for it. Anyway, just thought I'd throw that info in.
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