As a new employee starting his first job, the young newcomer is assigned to work alongside Ruru and Yoshinaga at a beverage company, visiting retail stores. Though adored by the female staff, he's actually shy around women—a pitiful junior struggling with his insecurities. To help him gain confidence, his senpai take matters into their own hands, stripping off their blouses and using their big tits as they guide him through a practice session of grinding in the cowgirl position. Things escalate quickly as underwear comes off and boundaries blur. Overwhelmed by Ruru's sexy body, the rookie loses control. Accidentally touching his cock, she triggers an uncontrollable cumshot, resulting in a massive creampie.