Tsukumo works hard at her part-time job at a convenience store to earn money for her favorite band and dates with her boyfriend. However, the manager of the part-time job is a typical Showa-era pervert who keeps messing with Tsukumo and having fun by himself. One day, when Tsukumo goes to work, she witnesses the manager stroking his dick in the back room... Tsukumo is shocked to see something she didn't want to see, but what's more, she is shaken by the size of the manager's dick. Invaded by the manager's clutches, she becomes a cock-crazed man... Even though her boyfriend is nearby, she sucks the manager's big dick. The more she fucks during the shift, the more greedy the female part-timer in uniform becomes... She needs to replenish her balls with sperm while refilling her drinks, or her sperm stock won't keep up with the age difference sex