Ryota, who was living a normal life, went to visit the art museum because of the art museum ticket given by his teacher. I don't know if it was an accident or accident, but she fell into "The Room of the Deep Sea" and began to adventure in this art museum... Longing to go home, she vowed to return to the real world. In the art gallery, I meet the mysterious man Garry and the yellow-haired girl Yuer, and start an adventure together... Can we finally return to the real world?