On her first visit to a brothel, she unexpectedly met her mother; during incestuous relations, she ejaculated in a bubble bath. (Yoko Tsuki, VAGU-035)

Kazuya wanted to try out a mature women's bubble bath after receiving his part-time job paycheck. However, the bubble bath hostess who greeted him was none other than his mother, who had just been at home… He was about to turn around and leave when his mother said, "I'm the top hostess at this place. Since you're already here, why don't you enjoy yourself?"