Yuna Hasegawa is beautiful enough to make strangers turn around in the street, but her limited experience with men has always troubled her. The few partners she dated were passive, and she never felt sexually satisfied; her current husband is equally unenthusiastic in bed. One day, being groped on a train awakens a hidden kink. Unable to forget the excitement, she repeatedly relives the encounter until her pussy aches, and her overflowing sexual desire finally leads her to volunteer for porn.