Mami, who works at the same convenience store as her boyfriend, starts to feel uneasy about their sex life due to the lack of penetration. One day, she gets caught having sex during a break and is scolded, but that's when she catches a glimpse of the manager's massive cock. Driven by an insatiable curiosity for his big dick and her overwhelming sexual desire, she relentlessly seduces him even while at work, demanding sex.