The fourth installment in the series features Reiko, a smart and poised schoolgirl. Her daily school life is filled with erotic developments, such as being touched in the crotch by her teacher and masturbating standing up in the changing room. The biggest highlight, however, is the intense sex scene with her older brother while still wearing her school uniform—an absolutely shocking moment. Packed with realistic footage of audible swallowing and pure arousal, this title is a must-watch for sister fetish fans.