Ushio Aotsuki is a stubborn middle school student and son of an eccentric temple priest who goes about life without care for his father's claims regarding otherworldly monsters known as youkai. However, as he is tending to the temple while his father is away on work, his chores lead him to a shocking discovery: in the basement he finds a menacing youkai impaled by the fabled Beast Spear. The beast in question is Tora, infamous for his destructive power, who tries to coerce Ushio into releasing him from his five hundred year seal. Ushio puts no trust in his words and refuses to set him free. But when a sudden youkai outbreak puts his friends and home in danger, he is left with no choice but to rely on Tora, his only insurance being the ancient spear if he gets out of hand. Ushio and Tora's meeting is only the beginning of the unlikely duo's journey into the depths of the spiritual realm. With the legendary Beast Spear in his hands, Ushio will find out just how real and threatening the world of the supernatural can be. [Written by MAL Rewrite]

Following their heroic efforts at Walter Park, the students of the misfit class return to Babyls Demon School after their summer vacation. What awaits them is not only adoration and admiration but also the shocking revelation that, in order to stay in the luxurious Royal One classroom, the entire class must be promoted to Dalet rank before entering the second year. As the Harvest and Music Festivals are right around the corner, there seem to be ample opportunities to rank up. Doing so will not be simple, however, as no class thus far has managed to accomplish such a feat. Hoping to give the misfit class a chance to achieve the improbable, the school appoints special tutors to aid in confronting the challenges that lie ahead. With his sights set beyond Dalet, Iruma Suzuki decides to take strides toward the goal of ranking up, starting with gaining acknowledgement from his special tutor: the short-tempered and selfish Bachiko Barbatos.

In Stern Bild City, those with special abilities are called "NEXT," and can use their powers for good or bad. A unique organized group of NEXT appear regularly on Hero TV, where they chase down evildoers to bring limelight to their sponsors and earn Hero Points in the hopes of becoming the next "King of Heroes." Kotetsu T. Kaburagi, known as "Wild Tiger," is a veteran hero whose performance has been dwindling as of late, partially due to his inability to cooperate with other heroes. After a disappointing season in which most of the other heroes far outperformed Tiger, he is paired up with a brand new hero who identifies himself by his real name—Barnaby Brooks Jr. Barnaby, nicknamed "Bunny" by his frivolous new partner, quickly makes it clear that the two could not be more different. Though they mix as well as oil and water, Tiger and Bunny must learn to work together, both for the sake of their careers and to face the looming threats within Stern Bild. [Written by MAL Rewrite]

Eighteen-year-old Dale Reki is a skilled, kind, and respected traveller, acknowledged as one of the leading adventurers in the city of Kreuz. One day while on the hunt for magical beasts, he comes across a sweet devil girl named Latina. She is alone, dressed in rags, and bears the devils' symbol of a criminal: a broken horn. Concerned for her wellbeing, Dale decides to ensure Latina's safety by bringing her to his home, eventually leading to him adopting her. Latina is sweet, innocent and compassionate, charming Dale beyond his expectations. He begins to enjoy the life of parenthood— experiencing the trials that come with raising a child and coping with the heartache he feels whenever his busy lifestyle as an adventurer parts him from her. Although work and life as a new parent become reassuring constants for Dale, the mysteries surrounding the girl remain. Why was Latina alone in the forest, and why does she harbor the symbol of a criminal? At the same time, Latina also begins to learn about the world and herself as she adjusts to her new life with Dale. [Written by MAL Rewrite]