19-year-old Marina, a medical student. It had been two years since her last sexual encounter, leaving her nearly as virginal as one could be. Despite her academic knowledge of the human body, she possesses almost no understanding of sexual intercourse. Her vaginal fluids, churned into a white froth by repeated thrusting, mix thoroughly with the sperm ejaculated inside her without warning, becoming indistinguishable. This film captures how her first experience unfolds.