My name is Toma Hikaru. I go to Izumo Gakuen High School with my younger sister-in-law Miyuki, my childhood friend Nanami-chan, and Nagisa who thinks of me as a rival. I began to have a strange dream of a beautiful, naked shrine maiden praying in a lake. I don’t know who she is but, somehow, I think I know her. I also see a strange room within Izumo Gakuen in my dream. Feeling uneasy, I decide to sneak into the room. Little did I know that this was the beginning of a long journey.