Subaru Sumeragi is the thirteenth head of his powerful onmyouji clan. Until the time comes when he must fully succeed his grandmother, Subaru is permitted to live in Tokyo with his fraternal twin, Hokuto. While Subaru is kind and shy, Hokuto is full of exuberance, and her favorite pastime is designing bold matching outfits for the two of them to wear. Her next favorite activity is trying to set Subaru up with their veterinarian friend, Seishirou Sakurazuka, who, oddly enough, is always readily available to accompany the Sumeragis throughout the city. Subaru has to resolve a variety of spiritual conflicts in Tokyo: some are cases formally brought to him by clients, and others are matters in which he decides to involve himself. A selfless teenager, he empathizes with others to the point that their pain may as well be his own. This leaves him vulnerable in a city where nearly everyone makes decisions that only benefit themselves as individuals. Hokuto hopes that if Subaru develops feelings for Seishirou, their relationship will be the one thing that he never gives up for the sake of anyone else. However, is Seishirou the best candidate for her brother's love, or is he hiding sinister secrets?