When Herrin Amy is approached by a slave with a small dick, she tells him that he must have money to be in the same room with her. She knows that he will either pay or leave. When he stood there, she started telling him how inadequate he was and that his small dick meant that he wasn't a real man. She told him that in order for her to continue talking to him, she needed money and she watched him count off several large bills for her to go shopping.
When Princess Isabella is confronted with a small dicked slave, she makes him pay. She knows that a small dick can't give her any pleasure so he has to pay for the pleasure of her company. As long as she has to put up with his whining, she will make him pay. There isn't a day that goes by that he doesn't have to give her the money to even look at him.