Nina Yamada longs to fall in love with a cute boy who will protect her under any circumstances. While venting her frustrations to her friends, two handsome boys suddenly drop from the sky right before her eyes. They introduce themselves as Zero and Ichii, two candidates undergoing a magical trial to become professional wizards. As part of the assessment, the pair is assigned to locate the "Crystal Pearl" and guard it for six months against other applicants. Upon completion of the exam period, the duo holding the pearl will automatically qualify as full-fledged wizards. When the boys discover that Nina had accidentally mistaken the pearl for candy and swallowed it, they have no choice but to serve as her full-time bodyguards for the remainder of the exam until an antidote to extract the pearl can be developed. Protecting a human from their eccentric wizard candidate rivals proves far more challenging and exhausting than Zero and Ichii anticipated. Will they manage to pass the exam while keeping Nina alive?