Surrounded by a forest and a gated entrance, the Grace Field House is inhabited by orphans happily living together as one big family, looked after by their "Mama," Isabella. Although they are required to take tests daily, the children are free to spend their time as they see fit, usually playing outside, as long as they do not venture too far from the orphanage—a rule they are expected to follow no matter what. However, all good times must come to an end, as every few months, a child is adopted and sent to live with their new family, never to be heard from again. However, the three oldest siblings have their suspicions about what is actually happening at the orphanage, and they are about to discover the cruel fate that awaits the children living at Grace Field, including the twisted nature of their beloved Mama. [Written by MAL Rewrite]

The Mikadono sisters—Miwa, Niko, and Kazuki—stand at the pinnacle of Saika Academy as its Three Royals, renowned respectively as prodigies in shogi, karate, and theater. Unfortunately, they have drifted apart from each other due to their overwhelming dedication to their fields, effectively turning them into strangers living under the same roof. Enter Yuu Ayase, the son of the late Subaru Ayase, a legendary actress who graduated from Saika. Unlike his mother, Yuu lacks any extraordinary talent whatsoever, much to the disappointment of those who knew her. Still, he transfers to her alma mater with one quiet promise in his heart: to fulfill her final wish that he build a true and happy family. It just so happens that the Mikadono patriarch is also Subaru's longtime friend and benefactor, and he offers Yuu both a place to stay and a fresh start. Thrust into the lives of three estranged sisters who act cold toward him, Yuu may not be a genius himself, but the clumsy sincerity he brings might be what they all need to start anew.

Magano, a parallel realm filled with monsters known as "Kegare," is a place where exorcists deal with all impurities. Benio Adashino is a prodigy exorcist who is recognized for her strength and is summoned to Tokyo by the Exorcist Union. On her way, she plummets into the arms of Rokuro Enmadou, a young exorcist with a troubled past. But the impurities of Magano do not rest. When these two exorcists witness a couple of children stolen by a Kegare, Benio rushes to save them, dragging Rokuro along with her into Magano. Engaged in a fight she is on the verge of being defeated in, Benio is saved by Rokuro, revealing himself capable of being her rival in talent. Sousei no Onmyouji tells the story of two talented exorcists who are destined to become the "Twin Star Exorcists" and the prophesised parents of the Miko—the reincarnation of Abe no Seimei—who will cleanse the world of all impurities. [Written by MAL Rewrite]

Dreaming of changing the world for good, Akuto Sai transfers to Constant Magic Academy where he befriends a virtuous ninja clan member, Junko Hattori. On the way to the academy, they vow to make the world a better place together; however, the situation suddenly takes a turn for the worse upon his arrival—it is prophesied that he will become the Demon King! As word of his destiny spreads, the school begins to fear him, and Junko's trust in him falters. While Akuto is determined to not let his predicted future control his fate, it seems as though everything he says and does only serve to reinforce the fact that he is destined to be the Demon King. Moreover, he is surrounded by a harem of beautiful girls who each have their own plans for him, ranging from bringing him to justice to simply showering him with love. With his newly awakened powers, Akuto must cope with his constantly growing list of misfortune and fight to prove that his fate is not set in stone. [Written by MAL Rewrite]