Start getting him to do humiliating things for your amusement by offering little rewards. For example tell him that if he wants to stop wearing the lingerie he must...(e.g. Lick your asshole). If he wants the but plug out he has to show you what a good cock sucker he is by sucking your strap on. You can make him do as many tasks as you want, even if it's just for a tiny reward. The trick however is to actually reward him so he thinks your fair.