Akiyoshi Nakajima is a young man spurned by his girlfriend for perceived physical weakness and a lack of masculinity, driving him to seek strength and appeal through construction work. He joins a construction site anticipating demanding labor but steps into an unexpected workplace reality dominated by female colleagues. His assigned duties frequently diverge from building to providing sexual services for these women, who exhibit persistent interest in him.

He possesses brown hair and brown eyes, presenting a conventional appearance without distinctive features. His initial lack of athleticism clashes with the physically intense environment. Key coworkers include Hiroko Miike, the hiring manager assessing his stamina; Minako Takahara, a muscular figure embodying an Amazonian archetype; the tomboyish Akira Hayasaka; and an office assistant defined by intense sexual energy. One specific assignment involves negotiating with a neighboring adult manga artist disturbed by construction noise, pulling him further into unconventional situations.

Akiyoshi routinely experiences comedic subjugation by his coworkers, underscoring the series' erotic-comedic tone. His journey focuses on adapting to these pressures, with recurring attention on developing sexual endurance over physical strength. Events like losing a digging contest to Akira and reacting with exaggerated despondency illustrate his persistent struggles and the workplace's absurd nature. He views the environment as a bizarre parallel universe due to its eccentric dynamics and the peculiar expectations placed upon him. His life before the construction job remains unexplored beyond the initial rejection, and no evolution in his goals or personality is depicted across media.