"Night Warriors - Darkstalkers' Revenge" is a four-episode OVA series based on the Capcom fighting game franchise "Darkstalkers." The narrative centers on a supernatural conflict involving demons, monsters, and humans in a world where the boundaries between realms are blurred. The story begins with the resurrection of Pyron, an ancient cosmic entity intent on consuming Earth. His arrival disrupts the balance between the human world and the demon realm, drawing various supernatural beings into the fray.

The protagonist, Donovan Baine, is a dhampir—a half-human, half-vampire hybrid—who wields a sentient sword named Hiryu. Donovan is driven by a sense of justice and a desire to protect humanity from the chaos unleashed by Pyron. Alongside him is Anita, a young girl orphaned by supernatural forces, whom Donovan has sworn to protect. Their journey intersects with other key characters, each with their own motivations and ties to the unfolding conflict.

Morrigan Aensland, a succubus and ruler of the Aensland clan, plays a pivotal role. Initially appearing as a carefree and flirtatious figure, Morrigan becomes deeply involved in the battle against Pyron, driven by her own sense of duty and pride as a powerful demon. Her rival, Lilith, a fragment of Morrigan's soul given independent form, adds complexity to the narrative as she seeks to assert her own identity.

Demitri Maximoff, a vampire with ambitions of conquering both the human and demon worlds, serves as a secondary antagonist. His schemes often clash with Pyron's goals, creating a dynamic power struggle. Other notable characters include Felicia, a catgirl with a kind heart who fights to protect her orphanage, and Huitzil, a warrior from the demon realm who seeks to restore balance by eliminating Pyron.

The plot unfolds through a series of battles and alliances as the characters confront Pyron and his minions. The narrative explores themes of identity, power, and the coexistence of humans and demons. The climax centers on a final confrontation with Pyron, where the characters must unite their strengths to prevent the destruction of Earth. The resolution ties up the immediate threat but leaves room for the ongoing struggles of its diverse cast, reflecting the interconnected nature of their world.