Yamikadou Meijirou, a normal high school student, unexpectedly becomes the rescuer of a demon. After a surprising sequence of events, he uncovers the Seal of Solomon imprinted on his tongue, a one-of-a-kind talent that gives him the power to control an array of magic and demon energies. The downside, however, is that each usage of his newfound abilities reduces his life span, leaving him with only three years to live.
Determined to extend his fate, Yamikadou sets out on a mission to find the twelve Starlight Maidens who display exceptional markings on their bodies. By creating a mutual agreement with them via his tongue at the location of his own emblem, he can salvage himself.
