While male slaves generally can't dance very well, Lady Edyn and Goddess Katy have scientifically determined that electrocuting a slave's cock and balls seems to improve their dancing ability. It gives them a little bit of extra swing in their step and sway in their hips to make it almost look acceptable. Or perhaps it just makes the spectacle all that more amusing to the girls as he suffers while they laugh. Clearly more tests must be performed, for science of course.