Girls enjoying a girls' night on a sleeper train are surprised by an unexpected encounter. Miku, already slightly drunk, starts off in a bad mood, but once the lights are turned off and the mood sets in, she suddenly becomes excited. Her panties mysteriously get wet, signaling she's fully ready. As she begins giving a blowjob while gazing at the night scenery outside the window, Miku's hip movements grow increasingly erotic. Before long, the thrusting intensifies, and they end up sweating profusely from the intense pleasure. This unforgettable experience becomes etched into their night together.