"Shin Megami Tensei Devil Children: Light & Dark" is a 2000 anime series based on the "Devil Children" spin-off of the "Shin Megami Tensei" franchise. The story is set in a world where humans and demons coexist, though tensions between the two groups often lead to conflict. The narrative centers on two protagonists, Akira and Rei, who are Devil Children—humans with the ability to summon and command demons. Akira wields the power of light, while Rei commands the power of darkness, and together they are tasked with maintaining balance between the human and demon worlds.

The plot begins with the sudden appearance of demons in the human world, causing chaos and fear. Akira and Rei are drawn into the conflict when they discover their unique abilities and are chosen by the enigmatic organization known as the "Devil Children Project." This group aims to prevent the destruction of both worlds by ensuring harmony between humans and demons. As the story progresses, Akira and Rei encounter various factions, including rogue demons seeking to dominate humans and extremist humans who wish to eradicate all demons. The protagonists must navigate these conflicts while uncovering the truth behind the sudden demonic incursions.

Throughout the series, Akira and Rei form alliances with both humans and demons, learning to harness their powers and grow stronger. They face numerous challenges, including battles against powerful demon lords and moral dilemmas about the nature of coexistence. The narrative explores themes of duality, cooperation, and the consequences of prejudice, as the protagonists strive to bridge the gap between the two worlds. The series concludes with Akira and Rei confronting the ultimate threat to both realms, testing their resolve and the strength of their partnership.

The main characters are defined by their contrasting yet complementary abilities and personalities. Akira, the light-aligned protagonist, is compassionate and idealistic, often seeking peaceful resolutions. Rei, aligned with darkness, is more pragmatic and willing to use force when necessary. Their dynamic drives much of the story, as they learn to balance their differences and work together. Supporting characters include a diverse cast of demons and humans, each with their own motivations and roles in the overarching conflict. The series blends action, fantasy, and moral exploration, offering a straightforward yet engaging narrative within the "Shin Megami Tensei" universe.