I have the daddy fantasy as well, though I seem to expand that to authority figures in general. Doctor, headmaster, even a personal trainer. I seem to lean towards the ones that would play a role in shaping my character or having a responsibility for my well being. That way if I were to stray from my path, there would be a humiliating scolding before my ultimate punishment which would consist of my bottom being bared, spanked and given a thorough cleaning out, possibly a butt plug inserted as a reminder as I stand with my nose buried in the corner to think about my actions. The ritual of it would play a powerful part, knowing and anticipating, dreading the next step once the rite had been initiated. The feelings that would conjure up.