When Christin tells her slave to do something, she expects total obedience. When they don't obey, they have to be punished. She puts on her favorite black high heels and grabs his favorite toy robots and puts them on the rug in front of him. She steps on them, crushing them as he watches. She gets turned on and wet as she watches his face. She knows that he will learn to do as she says from this point forward. Or she will crush more toys.