Sissification also involves mind control through erotic hypnosis in which the sissy-in-training watches videos that glorify the process of worshiping giant cocks that put the would-be sissy’s pathetic little “clitty”—i.e., tiny penis—to shame. He is sternly instructed to gain sexual satisfaction from prostate stimulation rather than penile stimulation and is trained to achieve “sissygasms” by either sitting on dildos or being fucked in the ass.
Source: wiktionary