Asahi Mizuno and Oshima, who work in the same office, are secretly engaged in a passionate affair, seeking each other's bodies without regard for others watching. Both have families and cannot meet freely, yet they share one common desire: to forget everything, even just once, and lose themselves completely in sex. To fulfill this longing, they've spent months planning a clandestine trip disguised as a business assignment. Finally, the day arrives. Meeting at the station, they shed their suits, change into casual clothes, board the express train, and upon reaching the inn, immediately lock lips in a fierce embrace. What follows is an unforgettable night driven by uncontrollable desire and burning passion.