"D-Live!!" is a science fiction manga series written and illustrated by Ryōji Minagawa. The story is set in a near-future world where humanity faces an existential threat from mysterious alien entities known as "Visitors." These beings possess the ability to manipulate time and space, creating anomalies that disrupt the natural order. To combat this threat, the United Nations establishes a specialized task force called the "D-Live" team, composed of individuals with unique abilities to perceive and interact with the Visitors.

The protagonist, Shūichi Kagaya, is a high school student who becomes involved with D-Live after discovering his latent ability to detect Visitors. Unlike others, Shūichi can see the Visitors' true forms, which are invisible to most humans. This ability makes him a valuable asset to the team, though his inexperience and reluctance to embrace his role create tension. As the story progresses, Shūichi is thrust into increasingly dangerous missions, where he must confront not only the Visitors but also the moral and ethical dilemmas posed by their existence.

The narrative explores the dynamics within the D-Live team, which includes a diverse cast of characters, each with their own motivations and backstories. Among them is Ayumu Kurosaki, a skilled operative with a pragmatic approach to dealing with the Visitors, and Yūko Asahina, a scientist who provides technical support and seeks to understand the Visitors' origins. The team's interactions reveal the complexities of their mission, as they grapple with the consequences of their actions and the blurred line between humanity and the alien entities they fight.

As the series unfolds, the true nature of the Visitors is gradually revealed, raising questions about their purpose and connection to humanity. The story delves into themes of coexistence, identity, and the limits of human understanding, as the D-Live team uncovers deeper layers of the conflict. The narrative is driven by a mix of action, mystery, and philosophical inquiry, with each arc building on the stakes and expanding the scope of the world.

Shūichi's growth as a character is central to the story, as he evolves from a reluctant participant to a determined leader. His journey is marked by personal challenges, including the loss of allies and the discovery of his own connection to the Visitors. The series balances its high-stakes plot with moments of introspection, exploring the emotional toll of the conflict on its characters.

"D-Live!!" combines elements of science fiction and psychological drama, creating a narrative that is both engaging and thought-provoking. The series' exploration of its central conflict, coupled with its well-developed characters, makes it a compelling addition to the genre.