The "Train" setting is an incredibly common trope within Japanese lifestyle and entertainment media. The daily commute is a defining element of urban life, making it a powerful backdrop for dramatic storytelling.
The keyword string formats a specific product identifier or catalog entry for an audio drama, visual novel, or localized voice work (often identified by the "RJ" prefix common to Japanese digital distribution platforms like DLsite). The specific entry corresponds to an ASMR or audio drama release focusing on realistic situational sound design.