"12 Kagetsu" is a manga series that intertwines elements of romance, drama, and supernatural themes. The narrative centers around a young girl named Kaho, who discovers she has the ability to see and communicate with spirits. This ability becomes pivotal when she encounters a mysterious boy named Shigure, who is not entirely human. Shigure is bound to a curse that transforms him into a monstrous form during the night, and he seeks to break this curse before it consumes him entirely.

Kaho and Shigure form a bond as they work together to uncover the origins of his curse. Their journey leads them to a series of interconnected mysteries involving other supernatural beings and ancient rituals. Along the way, they encounter allies and adversaries, each with their own ties to the supernatural world. The story delves into themes of sacrifice, redemption, and the complexities of human emotions, as Kaho and Shigure navigate their growing feelings for each other amidst the chaos.

The plot is structured around a timeline of twelve months, with each chapter corresponding to a specific month. This temporal framework adds a sense of urgency to their quest, as the curse's progression is tied to the passage of time. The narrative explores the consequences of past actions and the impact of choices made in the present, creating a layered and intricate storyline.

Key characters include Kaho, whose empathy and determination drive much of the plot; Shigure, whose struggle with his dual nature forms the emotional core of the series; and a cast of supporting characters who provide depth and complexity to the world. The interactions between these characters are central to the development of the story, as their relationships evolve and influence the outcome of their journey.

"12 Kagetsu" combines a compelling supernatural mystery with a poignant exploration of human emotions, making it a distinctive entry in the genre. The series balances moments of tension and action with quieter, introspective scenes, creating a narrative that is both engaging and emotionally resonant.