Mion Sonoda works in the general affairs department of an underwear manufacturer. With a strong upward drive, she demonstrates her innate abilities. She is able to transfer to her long-desired product development department and is selected as a project member for the "New Underwear Launch" project. Even before that, she was targeted by sexual harassment from business partners and senior superiors, and despite being forced into quasi-sexual acts for promotion, she reluctantly accepted them... Further trials assail her... Enduring humiliation and shame in a black company... Gradually becoming pleasure...?