One day, office worker Kanae (Mia Masaka) witnesses a junior colleague being molested on the train to work. Kanae is concerned, but the junior colleague makes an unbelievable statement: "I was scared at first, but then I felt like I was being violated by a wild beast and got wet." Kanae puts up a strong guard to protect herself from the molester, but there's no way the beast can miss Kanae's big breasts. As she is relentlessly toyed with on the train on her way to and from work, before she knows it, her body can no longer survive without being molested...