"Kieli" is a manga series set in a dystopian, war-torn world where remnants of advanced technology and supernatural elements coexist. The story centers on Kieli, a young girl who possesses the ability to see and communicate with spirits, a trait that isolates her from others. Her life takes a dramatic turn when she encounters Harvey, an undead soldier cursed with immortality after being experimented on during the war. Harvey, who carries the guilt of his past and a deep sense of detachment from the world, reluctantly becomes Kieli's companion.

The narrative unfolds as Kieli and Harvey embark on a journey across a desolate landscape, traveling by train and encountering various spirits, remnants of the war, and other supernatural phenomena. Their journey is driven by Kieli's desire to understand the world and Harvey's search for redemption. Along the way, they are joined by the Corporal, the spirit of a soldier who resides in a radio and serves as a guide and protector to Kieli. The trio forms an unlikely family, navigating the complexities of their shared pasts and the harsh realities of their world.

Themes of loss, identity, and the consequences of war are woven throughout the story. Kieli's innocence and determination to connect with others contrast with Harvey's cynicism and emotional scars, creating a dynamic interplay between the characters. The series explores the lingering effects of conflict on both individuals and society, as well as the struggle to find meaning in a fractured world. The supernatural elements, such as spirits and undead soldiers, serve as metaphors for unresolved trauma and the persistence of memory.

As the story progresses, Kieli and Harvey's bond deepens, and they confront their own vulnerabilities and fears. The series balances moments of quiet introspection with action and mystery, as the characters uncover secrets about the war, the experiments that created beings like Harvey, and the true nature of the spirits that inhabit their world. The narrative builds toward a poignant exploration of redemption, forgiveness, and the possibility of finding hope amidst despair.