On May Day, sweaty workers revolt against Mio Kuroki, who inherited a small factory buried in debt. Mio is a beautiful, G-cup boss who works in a suit and desperately tries to rescue the factory her father left behind. But to the employees covered in sweat and grime, it looks like she only handles the easy work. Their wages have barely been paid, and their anger finally explodes. With the same filthy hands that gripped their monkey wrenches, they shamelessly grope their female boss's huge breasts.