Step-Mommy is tired of changing your stinky diaper, so she will punish you for being so messy. She is gonna make you sniff her wet and messy diaper. She tells you to do it, but she notices that your cock gets hard by doing it. She gets confused cause she thought you were too little for this kind of things, but that makes her horny too. So she starts to hump the chair while her step-son watches her and jerks to her.