The "RJ390136.mp3" file you have is likely a specific track or the full combined audio from this release. Because these files are often shared or archived under their DLsite ID, the code serves as the primary way for listeners to identify the specific voice actress and circle involved.
Discipline, "Wakarase" (making someone "understand" or submit), and heavy use of binaural sound effects. RJ390136.mp3
The audio follows a "Messugaki" (impudent/bratty girl) trope common in Japanese subculture. The narrative focuses on "disciplining" a bratty character who initially mocks the listener but is eventually overwhelmed through various adult-oriented scenarios. The "RJ390136