Step-Daddy! How long have you been watching me? Is that a boner in your pants?! Why? My feet? Step-Daddy, are you a foot pervert? How have I never noticed? Oh my god, I can use this to get whatever I want. Are you looking at them right now? I bet youd love for me to rub my soft feet all over your cock, wouldnt you? You are going to do anything I say now, arent you? Just think of what I could tell everyone about this! Look at my pretty shiny feet and jerk off! I need some proof.

Step-Daughter discovers your foot fetish, teases, then blackmails you.