It has been 10 years since Heaven's Gate appeared in South America and Hell's Gate appeared in Japan, veiling the once familiar night sky with an oppressive skyscape. Their purposes unknown, these Gates are spaces in which the very laws of physics are ignored. With the appearance of the Gates emerged Contractors, who, in exchange for their humanity, are granted supernatural abilities. In the Japanese city surrounding Hell's Gate, Section 4 Chief Misaki Kirihara finds herself at odds with an infamous Contractor codenamed Hei. Called Black Reaper in the underground world, Hei, like his associates, undertakes missions for the mysterious and ruthless Syndicate while slowly peeling back the dark layers covering a nefarious plot that threatens the very existence of Contractors. From the mind of Tensai Okamura comes a sci-fi thriller taking the form of a subtle exposé on a war in which political positions and justice have no sway—a war waged exclusively in the shadows.

War(Date), resumes. The peaceful days of Itsuka Shidou returned without having to save the Spirits from the relentless battle days. But, the peaceful days were interrupted by the emergence of a mysterious sphere emitting spiritual wave――as well as a mysterious girl who showed herself at the same time. What is her purpose of keeping an eye on Shidou……? The mission that had been entrusted to Shidou under the tense situation was, “Date all of the Spirits, and make them fall in love?!” ――With the fate of humanity at stake, the war(date) resumes! (Source: Date A Live Wiki)

Despite the numerous challenges he has overcome so far, Shidou Itsuka's mission with Ratatoskr is far from over. In a departure from his daily routine, Shidou encounters a starving woman lying on the street and ends up helping her. After the two arrive at her apartment, the woman introduces herself as Nia Honjou—a popular manga artist working under a pen name. However, cutting straight to the chase, Nia reveals that she is also a Spirit and is aware of Shidou's secret operation. Interested in seeing his charisma firsthand, Nia challenges Shidou to win her over on a date. As he strives for an opportunity to seal her powers, Shidou learns more about Nia and her history with Deus Ex Machina Industries, a name he is all too familiar with...

Soon after falling into another world, Kurumi Tokisaki takes interest in a particular white cat. Much to Kurumi's disappointment, the two part ways. Kurumi later meets Hibiki Higoromo, a white haired quasi-spirit. Hibiki explains that they are at the center of a killing game between quasi-spirits. Within the Neighboring World, the spirits compete for a single wish to be granted to the lone survivor of the death-match. Understanding the rules of the game, Kurumi and Hibiki reach a compromise—a temporary alliance.