After passing away, a Japanese office worker finds himself reincarnated in another world as Ars, the newborn son of the noble Louvent family. The Summerforth Empire, where the Louvents rule over a small territory of a few thousand people, is a medieval-like land plagued by social inequality and political instability. As Ars grows older and learns more and more about his new environment, he becomes convinced that war will soon erupt. Fortunately, though Ars was not blessed with unrivaled strength or extraordinary magical aptitude, he does possess Appraisal: a seemingly unique skill that allows him to instantly grasp someone's current abilities and latent talents merely by looking at them. In an effort to prepare his domain for the imminent strife, Ars resolves to enlist the most exceptional people he can find, paying no attention to superficial qualities like race or social status.

No longer concerned with military affairs, Yukichi Fukuzawa intends to act as a lone bodyguard-for-hire, making use of his deadly swordsmanship. However, things are not going as planned for his freelance business, and that is when he crosses paths with a mouthy boy named Ranpo Edogawa. While their initial interactions are intertwined with a bizarre murder mystery, the aftermath prompts the formation of the Armed Detective Agency. Presently, Ranpo finds himself chasing down a gifted individual with the dangerous ability to execute the perfect crime. But as the great detective unravels the case, he soon discovers an elaborate plot to obliterate the Agency in its entirety. Although forewarned of the trap, the Agency continue their pursuit of the criminals, only to end up framed for the crime themselves. Now branded as wanted terrorists, the remaining members must find a way to prove their innocence—even if they must turn to sworn enemies for assistance.

In a world where the Demon King has died, a host of demigods capable of felling him have inherited the world. A master fencer who can figure out how to take out their opponents with a single glance; a lancer so swift they can break the sound barrier; a wyvern rogue who fights with three legendary weapons at once; an all-powerful wizard who can speak thoughts into being; an angelic assassin who deals instant death. Eager to attain the title of "True Hero," these champions each pursue challenges against formidable foes and spark conflicts among themselves. The battle to determine the mightiest of the mighty begins.

An OVA that will be bundled with the seventh volume of the Shinmai Maou no Testament manga, to be released January 2016.