London, the city of magic. In this city shrouded by mist, Elliott and his assistant— "No, wait. Super cute assistant. It's important to Alicia-chan,“—and his super cute assistant Alicia, made a name for themselves as the only ”detective with a wizard's license" in the British Empire. Usually, wizards don't take on detective jobs. It's all to find his missing brother and restore Alicia's life as Angelica. Three years ago, she was killed by Elliott's older brother. It was a magical murder that erased every trace of her existence from the world. To save her, Elliott broke a taboo, and then… lost his magic. In the blood-stained room, he swore. “I'll give my soul to the devil if I have to, but I will bring her back.” (Source: Dengeki Bunko, translated)