Juicy Imouto☆Hentai Pakorikkusu: Mezase! Motekawa H na Onna no Ko♪

Ohana, a naive younger sister, bursts into her older brother Kouichirou's room after taking a magazine article at face value, declaring her desire to become a "little devil girl." Unbeknownst to her, Kouichirou has secretly been using her as masturbation material every night. He seizes the opportunity to propose a series of naughty training sessions.

His foolish sister happily agrees, and Kouichirou indulges in various acts including blowjobs, anal, outdoor sex, and cosplay. The story follows their increasingly explicit encounters as Ohana learns to embrace her newfound role.