Inversion Therapy is a psychological program created by Darius Fontaine. He tells people to "Face Your Fears". This is heard in adverts (and a segment on Entertaining America) on the radio in Grand Theft Auto: San Andreas. Examples of people facing their fears are a mother who was afraid of her children getting hurt, so she stabbed them so it wouldn't bother her anymore, and a man who was afraid of sleeping with his mother and now that he has done it doesn't want to anymore. On Entertaining America, the Epsilon Program's leader Cris Formage and Fontaine are shown to have a rivalry. Lazlow implies that he slept with his mother on Fontaine's advice, leading him to get a restraining order, and Formage tells Fontaine to "Kiss my ass".
References in other games
Beatrix Fontaine is a fortune teller from Grand Theft Auto IV. There is a possibility of relation, though unlikely, and both radio personalities practice fraudulent self-help schemes.