Scene 1: Yuka shows up at an artist drawing class as a nude model, gets dressed and starts posing for the students. The class teacher convinces her to let him cover her in oil, which he brushes over her body. (No sex).
Scene 2: She returns to the dressing area and starts to masturbate as the aphrodisiac oil kicks in. The class teacher returns in the middle of her playing with herself. She sucks him, fucks him, and finishes with a facial.
Scene 3: Returning to the classroom, Yuka is once again covered in the aphrodisiac oil. She can't resist sucking a cock that's offered to her, and the gangbang begins. Fucking and sucking in a variety of positions with cumshots on her face and tits.
Note: This is my favorite film by this actress. The movie is made at the 59 minute mark, where Yuka spends five minutes trying to keep her lips off of the cock of her partner before finally giving in and sucking him off in front of the class.