"Bible Black: New Testament" is a sequel to the original "Bible Black" series, continuing its dark and supernatural themes. The narrative revolves around a cursed grimoire, the Bible Black, which grants its wielder immense power at a grave cost. The story begins with a new protagonist, Minoru Muroi, a high school student who becomes entangled in the occult after discovering the grimoire. Minoru's curiosity leads him to experiment with the book's dark magic, unleashing a series of supernatural events that spiral out of control.

The plot explores the consequences of Minoru's actions as he delves deeper into the occult. The grimoire's influence corrupts those around him, including his classmates and teachers, leading to a series of disturbing and tragic events. Minoru's journey is marked by his struggle to understand the full extent of the grimoire's power and his attempts to mitigate the chaos it causes. The narrative is driven by themes of temptation, corruption, and the moral dilemmas associated with wielding forbidden knowledge.

Key characters include Minoru Muroi, whose descent into darkness serves as the central focus of the story. Other significant figures include his classmates, who are drawn into the grimoire's influence, and various occult practitioners who either aid or hinder Minoru's efforts. The series maintains a tense and foreboding atmosphere, with its plot twists and supernatural elements keeping the narrative engaging.

The storyline is structured around episodic arcs, each focusing on different characters and their interactions with the grimoire. These arcs contribute to the overarching plot, building tension and complexity as the series progresses. The series concludes with a climactic resolution that ties together the various threads of the narrative, leaving a lasting impact on the characters and their world.