The problem is without a cage, every time hubby gets aroused or feels the urge he masturbates, and then becomes uninterested in sex for some time. By caging he is unable to get erect and ejaculate so he is always aroused. This makes him more agreeable to whatever his wife wants from him. Being aroused he is always keen to provide her with oral pleasures, and this includes oral cleanup after she has been fucked by her lover. Many are also easily aroused by any sexual activity and soon learn to enjoy sucking her lovers cock, guiding her lover in and cleaning her lovers cock after he has pleasured the wife. In return he can earn a release.