"Rokudenashi Majutsu Koushi to Akashic Records," commonly known as "Akashic Records of Bastard Magical Instructor," is a fantasy anime series set in a world where magic is a fundamental part of society. The story unfolds at the Alzano Imperial Magic Academy, a prestigious institution where young magicians are trained. The narrative centers on Glenn Radars, a lazy and unmotivated individual who is unexpectedly hired as a substitute magical instructor for Class 2 of the academy. Despite his lack of enthusiasm and unorthodox teaching methods, Glenn possesses a mysterious past and exceptional magical abilities.

The series introduces Sistine Fibel, a diligent and serious student who initially despises Glenn for his carefree attitude and apparent incompetence. Alongside her is Rumia Tingel, Sistine's best friend and a kind-hearted girl who harbors a significant secret: she is the vessel for the resurrected Demon Lord, a figure of immense power and danger. As Glenn begins to teach the class, his unconventional approach gradually reveals his depth of knowledge and skill, earning the respect of his students. However, his past as a former member of the Imperial Court Mage Corps, known as "The Fool," comes to light, intertwining his fate with the academy's present challenges.

The plot thickens as the academy becomes the target of various threats, including a secretive organization seeking to exploit Rumia's latent powers. Glenn, Sistine, and their classmates are drawn into a series of conflicts that test their abilities and resolve. The narrative explores themes of trust, redemption, and the responsibilities of power, as Glenn confronts his past and strives to protect his students. The series balances action, humor, and emotional moments, with Glenn's growth as a mentor and protector serving as a central arc.

Key characters include Sistine Fibel, whose determination and strong moral compass drive much of the story's progression, and Rumia Tingel, whose internal struggle with her dual identity adds depth to the narrative. Other notable characters include Albert Frazer, Glenn's former comrade and a skilled swordsman, and Re=L Rayford, a stoic and powerful mage with a complex relationship to Glenn. The interplay between these characters and their development throughout the series contribute to its engaging and dynamic storytelling.