When 14-year-old Koizumi Yuta discovers he must mate with the princess of the magical realm, Lucia, to conceive a child capable of engulfing the world for a week, he faces a daunting challenge. Tasked with preventing this cataclysm are two angels, Mikamoto El and Kasukabe Rie, with whom Yuta harbors romantic feelings for Kasukabe Rie. How will Yuta navigate this extraordinary situation and emerge unscathed?