The Guts

Akiyoshi, a somewhat slim student, takes all his courage and reveals his affection for her to his girlfriend. Due to his slim physique he cannot land with her. Thereupon he decides to train his body, so that such a thing does not happen to him again. When he finds a piece of paper on which it says that employees are wanted for the construction, he decides to take this job. But in doing so, he has to pass a "practical test", which is supposed to test how high his "stamina" is. Little by little he realizes that he was not hired on a normal construction site, but that everything here is all about sex...