Ballbusting: Beat That Pathetic Sack of Nuts

My Slave is perfect for me. He does not want me to punish him lightly. He says, if I punish him too mildly, it feels like it's not real. And this Slave needs it to feel real. He needs to feel the throbbing between his legs. He craves it. Only, when it truly hurts, does it make his cock get rock hard. And I love my slave to have a happy cock :)