The GA, who works in the passenger compartment of an express train, is a childhood friend. As they get excited talking after meeting for the first time in a long time, the GA begins to discuss her sexual problems with her boyfriend, such as "I can't look at his dick properly" and "I can't have sex in a bright place." At the same time, she starts reaching for his dick with a serious look on her face, saying that she wants to overcome these problems... Even though it's been a long time, she is a childhood friend and has a boyfriend. The man is tempted by this...