In this adult sibling fantasy, seemingly perfect Rikka comes home after being dumped for lacking sexual technique. Her wounded pride makes her target the cock of the socially awkward grown brother she always treated as beneath her. A relentless 24-hour training session begins: demanding his cock first thing in the morning, sucking him during chores, licking his balls, and secretly riding him in his sleep. Practice turns into addiction, and the proud sister soon begs with a shameless face before finishing with a rapid series of creampies without ever letting him pull out.