Hanjuku Developer

The employees in research and development at a certain office equipment maker are all somewhat odd. There's small, baby-faced, big-breasted Rio Takadera and the ditzy genius Hatsuko Yamashina. And then there's the queen of human resources, Mari Oosumi.
Here are the woeful tales of these poor men who are wrapped around the fingers of these cute, but somewhat eccentric women. What will happen in the love lives of these researchers who are passionate about both work and sex?!

1-2. Up-down
3-5. Hanjuku Developer
6. Arrangement
7-9. Mankai♥Industry