After working all night, the humble office worker Takimoto gets his morning wood seen by the cleaner, Yui. Yui is invisible in the office, but Takimoto is excited by her voluptuous body, visible through her work clothes, and attacks her without thinking... Contrary to her plain looks, she is sexually frustrated and lets him cum inside her right away, and he has sex with the cleaner, who has a great pussy, while at work!