Your new psychiatrist tells you its totally normal to fantasize, but she doesn't know what you like. Or so you think.  Your step-mother spilled everything, it turns out: about catching you jerking off to that picture of your step-sister, about how you stole her panties...god, how embarrassing. But this doctor, or whatever she is, she tells you its perfectly normal to have attractions like that. Is she for real? She seems it. She also seems like maybe she's flirting a little. She starts telling you her own fantasies, and stories, too. About her sexual experiences, with her own step-brother. You don't want it to happen but your cock is getting really hard, and before long, your telling her things, admitting things, stroking your cock while she touches herself, encourages you to stroke, and confess, and fuck, god...to cum for her...