The Guts!

Akiyoshi Nakajima is a young man who has just been rejected by his girlfriend for not being athletic enough. The newly dumped Akiyoshi struggles to find a way to obtain a "strong and manly aura", and on an impulse, begins working at a construction site. However, he is shocked to find most of the other workers on this site are women. Many of these women take a special interest in Akiyoshi; much of his work on the site seems to be performing sexual services rather than building things.

Akiyoshi gets to know a number of his female coworkers - the hiring manager who wishes to test his "stamina", a buff bodybuilder woman who loves ribbing on her male coworkers, an oversexed office assistant, a girl who disguises herself as a male employee, and more. At one point, Akiyoshi is even sent out to deal with a tenant near the construction site, an adult manga artist who works nights and sleeps days, but can't sleep because of all the work nearby. Over the course of the series, Akiyoshi is intimately dominated by a variety of women, usually in a comical manner.