START-108 一位在牛肉盖饭连锁店工作的隐秘美人——一位兼职家庭主妇——与一名学生兼职员工发生婚外情，未采取避孕措施，对方在她体内射精。.

Yotsuba, a married woman who works as a burly boy at a beef bowl chain, becomes close to a college student who is a co-worker. Yotsuba is attracted to the earnest and sincere young man. One day, they go out drinking because they have the same commute time, and they end up having a relationship. After that, they continue to have sex at home after work, during their breaks, and even in the kitchen during business hours, and they realize that they are perfect physical chemistry…