Aoyama Takashi is a salesman who works in a company that exploits him. At first excited about finally gaining employment, he soon finds that his life as a salaryman is miserable. He is berated and hit by his superior, and forced to work unpaid overtime. Depressed and convinced that his joyless life is not worth living, Aoyama tries to throw himself in front of a train. However, he is saved by Yamamoto, a cheerful guy who claims to be Aoyama's childhood friend. Aoyama's life begins to change because of Yamamoto, but when he starts digging into Yamamoto's identity, he realizes that Yamamoto is not entirely what he seems.