Special tracking episode following the two step-siblings who had forbidden creampie sex behind the older sister's (=wife's) back! The pregnant older sister, worried about their somewhat distant and awkward relationship, invites them saying "Would you like to participate in a game to deepen the bond between step-siblings?" and brings them to a special studio! The super-virile husband who crossed the line with his high school girl step-sister through creampie sex is given an additional proposal: "If you secretly film yourself having sex with your step-sister at home again, you'll get an even higher cash prize!"

What was captured on camera was the step-sister's various expressions as she was confused by her step-brother's sexual advances but couldn't refuse... The step-siblings with perfect physical compatibility repeatedly commit adultery! The ideal family collapses due to lost reason as they engage in secret home affairs — successfully captured on hidden camera!