"What, you? A peeping Tom?" "Could you give me a glass of water?" This seemingly utterly disconnected and awkward exchange marked the first encounter between Izumi Tamano, an ordinary office worker living in Japan, and Fulong, who would later be hailed as the best and strongest king in the history of the Holy Kingdom of York-Zai.

During her bath, the bathroom window connected to a mysterious world. Izumi leisurely enjoyed her bath, bartering with various individuals who appeared outside the window, but she eventually became deeply involved in the fate of that world...

I was too lazy to come up with names, so I ended up giving them rather arbitrary ones.